<?xml version="1.0" encoding="us-ascii"?>
<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2019-10-28T14:56:01.9878339+00:00 -->
<!-- Version            : 5.0.0.208 -->
<!-- Package ID         : eeff1c9bdcf94594abc38328ec266e71 -->
<!-- Copyright (c) 2019 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <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_KoreanNationalTaxServiceMember" name="KoreanNationalTaxServiceMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <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_ContractExpirationYear" name="ContractExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <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_IncreasesDueToCashReceived" name="IncreasesDueToCashReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <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_TransferredToReceivablesFromUnbilledReceivables" name="TransferredToReceivablesFromUnbilledReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_IncreaseDecreaseInUnbilledReceivablesAbstract" name="IncreaseDecreaseInUnbilledReceivablesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
</xsd:schema>
