<SEC-DOCUMENT>0001104659-19-039633.txt : 20190708
<SEC-HEADER>0001104659-19-039633.hdr.sgml : 20190708
<ACCEPTANCE-DATETIME>20190708215004
ACCESSION NUMBER:		0001104659-19-039633
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190703
FILED AS OF DATE:		20190708
DATE AS OF CHANGE:		20190708

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Thompson Michael Shawn
		CENTRAL INDEX KEY:			0001705981

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-23125
		FILM NUMBER:		19946263

	MAIL ADDRESS:	
		STREET 1:		12525 CHADRON AVENUE
		CITY:			HAWTHORNE
		STATE:			CA
		ZIP:			90250

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			OSI SYSTEMS INC
		CENTRAL INDEX KEY:			0001039065
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				330238801
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		12525 CHADRON AVE
		CITY:			HAWTHORNE
		STATE:			CA
		ZIP:			90250
		BUSINESS PHONE:		3109780516

	MAIL ADDRESS:	
		STREET 1:		12525 CHADRON AVENUE
		CITY:			HAWTHORNE
		STATE:			CA
		ZIP:			90250
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-07-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001039065</issuerCik>
        <issuerName>OSI SYSTEMS INC</issuerName>
        <issuerTradingSymbol>OSIS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001705981</rptOwnerCik>
            <rptOwnerName>Thompson Michael Shawn</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>12525 CHADRON AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HAWTHORNE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90250</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, OSI Electronics</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-07-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1079</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3800</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares are restricted stock units issued to the Reporting Person pursuant to the OSI Systems, Inc. 2012 Incentive Award Plan. Vesting and amount of shares is subject to achievement of performance targets.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Michael Shawn Thompson</signatureName>
        <signatureDate>2019-07-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
