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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001005284-09-000012.txt : 20090113
<SEC-HEADER>0001005284-09-000012.hdr.sgml : 20090113
<ACCEPTANCE-DATETIME>20090113170103
ACCESSION NUMBER:		0001005284-09-000012
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090109
FILED AS OF DATE:		20090113
DATE AS OF CHANGE:		20090113

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mahon Janice K
		CENTRAL INDEX KEY:			0001423446

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12031
		FILM NUMBER:		09524404

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		609-671-0980

	MAIL ADDRESS:	
		STREET 1:		C/O UNIVERSAL DISPLAY CORPORATION
		STREET 2:		375 PHILLIPS BLVD.
		CITY:			EWING
		STATE:			NJ
		ZIP:			08618

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			UNIVERSAL DISPLAY CORP \PA\
		CENTRAL INDEX KEY:			0001005284
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRONIC COMPONENTS & ACCESSORIES [3670]
		IRS NUMBER:				232372688
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		375 PHILLIPS BOULEVARD
		CITY:			EWING
		STATE:			NJ
		ZIP:			08618
		BUSINESS PHONE:		6096710980

	MAIL ADDRESS:	
		STREET 1:		375 PHILLIPS BOULEVARD
		STREET 2:		375 PHILLIPS BOULEVARD
		CITY:			EWING
		STATE:			NJ
		ZIP:			08618
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-01-09</periodOfReport>

    <issuer>
        <issuerCik>0001005284</issuerCik>
        <issuerName>UNIVERSAL DISPLAY CORP \PA\</issuerName>
        <issuerTradingSymbol>PANL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001423446</rptOwnerCik>
            <rptOwnerName>Mahon Janice K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>375 PHILLIPS BLVD.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>EWING</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>08618</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP of Tech Commercialization</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-01-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>888</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9.37</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>19750</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares were withheld to satisfy a tax liability in connection with the vesting, on January 9, 2009, of 2,460 shares of restricted stock previously granted to Ms. Mahon.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Steven V. Abramson (by power of attorney)</signatureName>
        <signatureDate>2009-01-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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