-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 LVhlc+v+E3tq7tdGgZDRsD5v3lIYYShh0blbb8/AdrCzmj1u+CPBrcncRgrBWjkW
 9eaxy7sNP5yZ1Syi2MNQGA==

<SEC-DOCUMENT>0000354913-05-000018.txt : 20050104
<SEC-HEADER>0000354913-05-000018.hdr.sgml : 20050104
<ACCEPTANCE-DATETIME>20050104171121
ACCESSION NUMBER:		0000354913-05-000018
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050101
FILED AS OF DATE:		20050104
DATE AS OF CHANGE:		20050104

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KIERNAN BRIAN G
		CENTRAL INDEX KEY:			0001193095

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11152
		FILM NUMBER:		05508603

	MAIL ADDRESS:	
		STREET 1:		781 THIRD AVENUE
		CITY:			KING OF PRUSSIA
		STATE:			PA
		ZIP:			194061409

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			INTERDIGITAL COMMUNICATIONS CORP
		CENTRAL INDEX KEY:			0000354913
		STANDARD INDUSTRIAL CLASSIFICATION:	PATENT OWNERS & LESSORS [6794]
		IRS NUMBER:				231882087
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		781 THIRD AVE
		CITY:			KING OF PRUSSIA
		STATE:			PA
		ZIP:			19406-1409
		BUSINESS PHONE:		6102787800

	MAIL ADDRESS:	
		STREET 1:		781 THIRD AVE
		STREET 2:		2200 RENAISANCE BLVD STE 105
		CITY:			KING OF PRUSSIA
		STATE:			PA
		ZIP:			19406-1409

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERNATIONAL MOBILE MACHINES CORP
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-01-01</periodOfReport>

    <issuer>
        <issuerCik>0000354913</issuerCik>
        <issuerName>INTERDIGITAL COMMUNICATIONS CORP</issuerName>
        <issuerTradingSymbol>IDCC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001193095</rptOwnerCik>
            <rptOwnerName>KIERNAN BRIAN G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>781 THIRD AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>KING OF PRUSSIA</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19406-1409</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Standards Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-01-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7506</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>35937</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>766</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k) Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Acquired pursuant to the InterDigital Communications Corporation 1999 Restricted Stock Plan.</footnote>
        <footnote id="F2">As of the most recently published account statement dated December 28, 2004, the Reporting Person beneficially owned 766 shares of Common Stock pursuant to the InterDigital Communications Corporation Savings and Protection Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Rebecca Bridgeford Opher, Attorney-In-Fact for Brian G. Kiernan</signatureName>
        <signatureDate>2005-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----