<?xml version="1.0" encoding="us-ascii"?>
<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2021-08-03T14:04:07.4027180+00:00 -->
<!-- Version            : 5.0.1.648 -->
<!-- Package ID         : d069832f896d41c4b2a76bc42f17620f -->
<!-- Copyright (c) 2021 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="oled_IncomeTaxesLineItems" name="IncomeTaxesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_IncomeTaxesTable" name="IncomeTaxesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_AllocationOfWithholdingToNonKoreanPatentsMember" name="AllocationOfWithholdingToNonKoreanPatentsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_WithholdingAndInterestForLicensingAndRoyaltyPayments" name="WithholdingAndInterestForLicensingAndRoyaltyPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_WithholdingAndInterestForLicencingAndRoyaltyPaymentsPeriod" name="WithholdingAndInterestForLicencingAndRoyaltyPaymentsPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_StateAndForeignIncomeTaxReturnsSubjectToExaminationPeriodMinimum" name="StateAndForeignIncomeTaxReturnsSubjectToExaminationPeriodMinimum" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_StateAndForeignIncomeTaxReturnsSubjectToExaminationPeriodMaximum" name="StateAndForeignIncomeTaxReturnsSubjectToExaminationPeriodMaximum" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_PercentageOfRevenueRecordedFromSaleOfMaterials" name="PercentageOfRevenueRecordedFromSaleOfMaterials" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_PercentageOfRevenueRecordedFromProvisionOfServices" name="PercentageOfRevenueRecordedFromProvisionOfServices" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_UnbilledReceivablesNoncurrent" name="UnbilledReceivablesNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_BacklogAssociatedWithCommittedPurchaseOrdersFromCustomers" name="BacklogAssociatedWithCommittedPurchaseOrdersFromCustomers" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_NetIncreaseDecreaseInDeferredRevenue" name="NetIncreaseDecreaseInDeferredRevenue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_UnbilledReceivablesIncreaseDecreaseNet" name="UnbilledReceivablesIncreaseDecreaseNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_IncreaseDecreaseInUnbilledReceivablesAbstract" name="IncreaseDecreaseInUnbilledReceivablesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
</xsd:schema>
