<?xml version="1.0" encoding="us-ascii"?>
<!-- Created by Merrill Corporation -->
<!--XBRL document created with Merrill Bridge  8.2.0.61 -->
<!--Based on XBRL 2.1-->
<!--Created on: 10/26/2018 3:53:28 PM-->
<!--Modified on: 10/26/2018 3:53:28 PM-->
<xsd:schema elementFormDefault="qualified" attributeFormDefault="unqualified" targetNamespace="http://www.osi-systems.com/20180930" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:invest="http://xbrl.sec.gov/invest/2013-01-31" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:xl="http://www.xbrl.org/2003/XLink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:net="http://www.xbrl.org/2009/role/net" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ref="http://www.xbrl.org/2004/ref" xmlns:attributeFormDefault="unqualified" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:osis="http://www.osi-systems.com/20180930" xmlns:country="http://xbrl.sec.gov/country/2017-01-31" xmlns:us-gaap="http://fasb.org/us-gaap/2018-01-31" xmlns:us-types="http://fasb.org/us-types/2018-01-31" xmlns:dei="http://xbrl.sec.gov/dei/2018-01-31" xmlns:us-roles="http://fasb.org/us-roles/2018-01-31" xmlns:negated="http://www.xbrl.org/2009/role/negated">
  <xsd:annotation>
    <xsd:appinfo>
      <link:roleType roleURI="http://www.osi-systems.com/role/StatementCondensedConsolidatedBalanceSheetsUnaudited" id="StatementCondensedConsolidatedBalanceSheetsUnaudited">
        <link:definition>00100 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/StatementCondensedConsolidatedStatementsOfOperationsUnaudited" id="StatementCondensedConsolidatedStatementsOfOperationsUnaudited">
        <link:definition>00200 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncomeUnaudited" id="StatementCondensedConsolidatedStatementsOfComprehensiveIncomeUnaudited">
        <link:definition>00300 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited" id="StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited">
        <link:definition>00400 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentationPerShareComputationsDetails" id="DisclosureBasisOfPresentationPerShareComputationsDetails">
        <link:definition>40102 - Disclosure - Basis of Presentation - Per Share Computations (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentationFairValueDetails" id="DisclosureBasisOfPresentationFairValueDetails">
        <link:definition>40104 - Disclosure - Basis of Presentation - Fair Value (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBusinessCombinationsExplosiveTraceDetectionDetails" id="DisclosureBusinessCombinationsExplosiveTraceDetectionDetails">
        <link:definition>40202 - Disclosure - Business Combinations - Explosive Trace Detection (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBalanceSheetDetailsDetails" id="DisclosureBalanceSheetDetailsDetails">
        <link:definition>40301 - Disclosure - Balance Sheet Details (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsIntangibleAssetsSubjectToAmortizationDetails" id="DisclosureGoodwillAndIntangibleAssetsIntangibleAssetsSubjectToAmortizationDetails">
        <link:definition>40402 - Disclosure - Goodwill and Intangible Assets - Intangible Assets Subject to Amortization (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsIntangibleAssetsSubjectToAmortizationDetailsCalc2" id="DisclosureGoodwillAndIntangibleAssetsIntangibleAssetsSubjectToAmortizationDetailsCalc2">
        <link:definition>40402 - Disclosure - GOODWILL AND INTANGIBLE ASSETS - Intangible Assets Subject to Amortization (Details) Calc 2</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsIntangibleAmortizationDetails" id="DisclosureGoodwillAndIntangibleAssetsIntangibleAmortizationDetails">
        <link:definition>40403 - Disclosure - Goodwill and Intangible Assets - Intangible Amortization (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureRestructuringAndOtherChargesRestructuringAndOtherChargesDetails" id="DisclosureRestructuringAndOtherChargesRestructuringAndOtherChargesDetails">
        <link:definition>40501 - Disclosure - Restructuring and Other Charges - Restructuring and other charges (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBorrowingsDetails" id="DisclosureBorrowingsDetails">
        <link:definition>40601 - Disclosure - Borrowings (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureStockholdersEquityStockBasedCompensationDetails" id="DisclosureStockholdersEquityStockBasedCompensationDetails">
        <link:definition>40701 - Disclosure - Stockholders' Equity - Stock-based Compensation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureRetirementBenefitPlansDetails" id="DisclosureRetirementBenefitPlansDetails">
        <link:definition>40801 - Disclosure - Retirement Benefit Plans (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DocumentDocumentAndEntityInformation" id="DocumentDocumentAndEntityInformation">
        <link:definition>00090 - Document - Document and Entity Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/StatementCondensedConsolidatedBalanceSheetsUnauditedParenthetical" id="StatementCondensedConsolidatedBalanceSheetsUnauditedParenthetical">
        <link:definition>00105 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentation" id="DisclosureBasisOfPresentation">
        <link:definition>10101 - Disclosure - Basis of Presentation</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBusinessCombinations" id="DisclosureBusinessCombinations">
        <link:definition>10201 - Disclosure - Business Combinations</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBalanceSheetDetails" id="DisclosureBalanceSheetDetails">
        <link:definition>10301 - Disclosure - Balance Sheet Details</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssets" id="DisclosureGoodwillAndIntangibleAssets">
        <link:definition>10401 - Disclosure - Goodwill and Intangible Assets</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureRestructuringAndOtherCharges" id="DisclosureRestructuringAndOtherCharges">
        <link:definition>10501 - Disclosure - Restructuring and Other Charges</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBorrowings" id="DisclosureBorrowings">
        <link:definition>10601 - Disclosure - Borrowings</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureStockholdersEquity" id="DisclosureStockholdersEquity">
        <link:definition>10701 - Disclosure - Stockholders' Equity</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureRetirementBenefitPlans" id="DisclosureRetirementBenefitPlans">
        <link:definition>10801 - Disclosure - Retirement Benefit Plans</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureCommitmentsAndContingencies" id="DisclosureCommitmentsAndContingencies">
        <link:definition>10901 - Disclosure - Commitments and Contingencies</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureIncomeTaxes" id="DisclosureIncomeTaxes">
        <link:definition>11001 - Disclosure - Income Taxes</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureSegmentInformation" id="DisclosureSegmentInformation">
        <link:definition>11101 - Disclosure - Segment Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentationPolicies" id="DisclosureBasisOfPresentationPolicies">
        <link:definition>20102 - Disclosure - Basis of Presentation (Policies)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentationTables" id="DisclosureBasisOfPresentationTables">
        <link:definition>30103 - Disclosure - Basis of Presentation (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBusinessCombinationsTables" id="DisclosureBusinessCombinationsTables">
        <link:definition>30203 - Disclosure - Business Combinations (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBalanceSheetDetailsTables" id="DisclosureBalanceSheetDetailsTables">
        <link:definition>30303 - Disclosure - Balance Sheet Details (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsTables" id="DisclosureGoodwillAndIntangibleAssetsTables">
        <link:definition>30403 - Disclosure - Goodwill and Intangible Assets (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureRestructuringAndOtherChargesTables" id="DisclosureRestructuringAndOtherChargesTables">
        <link:definition>30503 - Disclosure - Restructuring and Other Charges (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBorrowingsTables" id="DisclosureBorrowingsTables">
        <link:definition>30603 - Disclosure - Borrowings (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureStockholdersEquityTables" id="DisclosureStockholdersEquityTables">
        <link:definition>30703 - Disclosure - Stockholders' Equity (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureRetirementBenefitPlansTables" id="DisclosureRetirementBenefitPlansTables">
        <link:definition>30803 - Disclosure - Retirement Benefit Plans (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureCommitmentsAndContingenciesTables" id="DisclosureCommitmentsAndContingenciesTables">
        <link:definition>30903 - Disclosure - Commitments and Contingencies (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureSegmentInformationTables" id="DisclosureSegmentInformationTables">
        <link:definition>31103 - Disclosure - Segment Information (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentationDescriptionOfBusinessDetails" id="DisclosureBasisOfPresentationDescriptionOfBusinessDetails">
        <link:definition>40101 - Disclosure - Basis of Presentation - Description of Business (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentationCashEquivalentsDetails" id="DisclosureBasisOfPresentationCashEquivalentsDetails">
        <link:definition>40103 - Disclosure - Basis of Presentation - Cash Equivalents (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentationRevenueRecognitionDetails" id="DisclosureBasisOfPresentationRevenueRecognitionDetails">
        <link:definition>40105 - Disclosure - Basis of Presentation - Revenue Recognition (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBasisOfPresentationRevenueRecognitionDefaultDetails" id="DisclosureBasisOfPresentationRevenueRecognitionDefaultDetails">
        <link:definition>40105 - Disclosure - Basis of Presentation - Revenue Recognition Default (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBusinessCombinationsFiscalYear2019BusinessAcquisitionsDetails" id="DisclosureBusinessCombinationsFiscalYear2019BusinessAcquisitionsDetails">
        <link:definition>40201 - Disclosure - Business Combinations - Fiscal Year 2019 Business Acquisitions (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBusinessCombinationsIntangibleAssetsDetails" id="DisclosureBusinessCombinationsIntangibleAssetsDetails">
        <link:definition>40203 - Disclosure - Business Combinations - Intangible Assets (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureBusinessCombinationsOtherBusinessAcquisitionDetails" id="DisclosureBusinessCombinationsOtherBusinessAcquisitionDetails">
        <link:definition>40204 - Disclosure - Business Combinations - Other Business Acquisition (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsGoodwillDetails" id="DisclosureGoodwillAndIntangibleAssetsGoodwillDetails">
        <link:definition>40401 - Disclosure - Goodwill and Intangible Assets - Goodwill (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureRestructuringAndOtherChargesChangesInAccrualForRestructuringAndOtherChargesDetails" id="DisclosureRestructuringAndOtherChargesChangesInAccrualForRestructuringAndOtherChargesDetails">
        <link:definition>40502 - Disclosure - Restructuring and Other Charges - Changes in the accrual for restructuring and other charges (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureStockholdersEquityShareRepurchaseProgramDetails" id="DisclosureStockholdersEquityShareRepurchaseProgramDetails">
        <link:definition>40702 - Disclosure - Stockholders' Equity - Share Repurchase Program (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureCommitmentsAndContingenciesContingentAcquisitionObligationsDetails" id="DisclosureCommitmentsAndContingenciesContingentAcquisitionObligationsDetails">
        <link:definition>40901 - Disclosure - Commitments and Contingencies - Contingent Acquisition Obligations (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureCommitmentsAndContingenciesProductWarrantiesDetails" id="DisclosureCommitmentsAndContingenciesProductWarrantiesDetails">
        <link:definition>40902 - Disclosure - Commitments and Contingencies - Product Warranties (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureIncomeTaxesDetails" id="DisclosureIncomeTaxesDetails">
        <link:definition>41001 - Disclosure - Income Taxes - (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.osi-systems.com/role/DisclosureSegmentInformationOperationsAndIdentifiableAssetsDetails" id="DisclosureSegmentInformationOperationsAndIdentifiableAssetsDetails">
        <link:definition>41101 - Disclosure - Segment Information - Operations and Identifiable Assets (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:linkbaseRef xlink:type="simple" xlink:href="osis-20180930_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="osis-20180930_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="osis-20180930_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="osis-20180930_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
    </xsd:appinfo>
  </xsd:annotation>
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2018-01-31" schemaLocation="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd" />
  <xsd:import namespace="http://fasb.org/us-roles/2018-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2018/elts/us-roles-2018-01-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <import namespace="http://fasb.org/us-gaap/2018-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd" xmlns="http://www.w3.org/2001/XMLSchema" />
  <import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" xmlns="http://www.w3.org/2001/XMLSchema" />
  <import namespace="http://fasb.org/srt/2018-01-31" schemaLocation="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="AmendedAndRestatedEquityParticipationPlan2006Member" id="osis_AmendedAndRestatedEquityParticipationPlan2006Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BalanceSheetDetailsDisclosureAbstract" id="osis_BalanceSheetDetailsDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessDescriptionAbstract" id="osis_BusinessDescriptionAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <element id="osis_CustomerOneMember" name="CustomerOneMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="CustomerRelationshipsOrderOrProductionBacklogMember" id="osis_CustomerRelationshipsOrderOrProductionBacklogMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DescriptionOfBusinessPolicyTextBlock" id="osis_DescriptionOfBusinessPolicyTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DocumentAndEntityInformationAbstract" id="osis_DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" id="osis_FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="GoodwillAcquiredOrAdjustedDuringPeriod" id="osis_GoodwillAcquiredOrAdjustedDuringPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <element id="osis_HealthcareDivisionMember" name="HealthcareDivisionMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="IncentiveAwardPlan2012Member" id="osis_IncentiveAwardPlan2012Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <element id="osis_InsuranceCompanyContractsFairValue" name="InsuranceCompanyContractsFairValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_LineOfCreditFacilityBorrowingCapacityAvailableIncrease" name="LineOfCreditFacilityBorrowingCapacityAvailableIncrease" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="LineOfCreditFacilitySublimitAvailableForLettersOfCredit" id="osis_LineOfCreditFacilitySublimitAvailableForLettersOfCredit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <element id="osis_MexicanGovernmentMember" name="MexicanGovernmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_OptoelectronicsAndManufacturingDivisionMember" name="OptoelectronicsAndManufacturingDivisionMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_PerformanceBasedRestrictedStockUnitsMember" name="PerformanceBasedRestrictedStockUnitsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="RestrictedStockAndRestrictedStockUnitsMember" id="osis_RestrictedStockAndRestrictedStockUnitsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <element id="osis_ScheduleOfBalanceSheetAccountsTableTextBlock" name="ScheduleOfBalanceSheetAccountsTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ScheduleOfFiniteAndIndefiniteLivedIntangibleAssetsByMajorClassTableTextBlock" name="ScheduleOfFiniteAndIndefiniteLivedIntangibleAssetsByMajorClassTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" id="osis_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <element id="osis_SecurityDivisionMember" name="SecurityDivisionMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantIncreasedForEachAwardForfeitedAndReturned" id="osis_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantIncreasedForEachAwardForfeitedAndReturned" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantReducedForEachAwardGranted" id="osis_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantReducedForEachAwardGranted" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" id="osis_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardWeightedAverageRemainingContractualTermAbstract" id="osis_ShareBasedCompensationArrangementByShareBasedPaymentAwardWeightedAverageRemainingContractualTermAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationByShareBasedPaymentAwardPerformanceBasedAwardsPayoutPercentage" id="osis_ShareBasedCompensationByShareBasedPaymentAwardPerformanceBasedAwardsPayoutPercentage" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedEmployeeCompensationPlansMember" id="osis_ShareBasedEmployeeCompensationPlansMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <element id="osis_CashPaidNetDuringPeriodAbstract" name="CashPaidNetDuringPeriodAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_SharesExcludedFromComputationOfDilutedNetIncomePerShareAbstract" name="SharesExcludedFromComputationOfDilutedNetIncomePerShareAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ShareRepurchaseProgramAbstract" name="ShareRepurchaseProgramAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ConcentrationRiskNumberOfCustomer" name="ConcentrationRiskNumberOfCustomer" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedPayrollAndRelatedExpenses" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedPayrollAndRelatedExpenses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAdvancesFromCustomers" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAdvancesFromCustomers" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesDeferredRevenue" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesDeferredRevenue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_NumberOfShareBasedCompensationAssumed" name="NumberOfShareBasedCompensationAssumed" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_AsE2005PlanAnd2014AsEPlanMember" name="AsE2005PlanAnd2014AsEPlanMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ConvertibleSeniorNotesDue2022Member" name="ConvertibleSeniorNotesDue2022Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_DebtIssuanceCostsDebtComponent" name="DebtIssuanceCostsDebtComponent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_DebtIssuanceCostsEquityComponent" name="DebtIssuanceCostsEquityComponent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_DebtInstrumentConvertiblePremiumOnStockPrice" name="DebtInstrumentConvertiblePremiumOnStockPrice" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_RestructuringPaymentsAndOtherAdjustments" name="RestructuringPaymentsAndOtherAdjustments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ScheduleOfImpairmentRestructuringAndRelatedCostsTableTextBlock" name="ScheduleOfImpairmentRestructuringAndRelatedCostsTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ComputerSoftwareImplementationInProcessMember" name="ComputerSoftwareImplementationInProcessMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ExplosiveTraceDetectionBusinessMember" name="ExplosiveTraceDetectionBusinessMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedWarranties" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedWarranties" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_BusinessCombinationAdditionOfContingentEarnOutObligations" name="BusinessCombinationAdditionOfContingentEarnOutObligations" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_EmploymentRelatedContingenciesAbstract" name="EmploymentRelatedContingenciesAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_DeferredCompensationArrangementWithIndividualContingentLiability" name="DeferredCompensationArrangementWithIndividualContingentLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_DeferredCompensationArrangementWithIndividualPaymentPeriod" name="DeferredCompensationArrangementWithIndividualPaymentPeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ChargesRelatedToLitigationMember" name="ChargesRelatedToLitigationMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ElectronicsComponentDesignerAndManufacturerMember" name="ElectronicsComponentDesignerAndManufacturerMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_OptoelectronicsSolutionsBusinessMember" name="OptoelectronicsSolutionsBusinessMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_TermOfContract" name="TermOfContract" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_InterestAndOtherExpenseNet" name="InterestAndOtherExpenseNet" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_RevenueRemainingPerformanceObligationExpectedTimingPercentage" name="RevenueRemainingPerformanceObligationExpectedTimingPercentage" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ContractWithCustomerLiabilityPercentageOfChangeCustomerDepositsAndPrepayments" name="ContractWithCustomerLiabilityPercentageOfChangeCustomerDepositsAndPrepayments" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ContractWithCustomerLiabilityPercentageOfChangeDeferredRevenueCurrent" name="ContractWithCustomerLiabilityPercentageOfChangeDeferredRevenueCurrent" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ContractWithCustomerLiabilityPercentageOfChangeDeferredRevenueNoncurrent" name="ContractWithCustomerLiabilityPercentageOfChangeDeferredRevenueNoncurrent" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_CxrLimitedMember" name="CxrLimitedMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ContractWithCustomerAssetPercentageOfChange" name="ContractWithCustomerAssetPercentageOfChange" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_ContractWithCustomerLiabilityCustomerDepositsAndPrepayments" name="ContractWithCustomerLiabilityCustomerDepositsAndPrepayments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_PrivatelyHeldServicesCompanyMember" name="PrivatelyHeldServicesCompanyMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="osis_BusinessCombinationContingentConsiderationArrangementsEarnedOutPeriod" name="BusinessCombinationContingentConsiderationArrangementsEarnedOutPeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
