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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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 mIQ9tIiHKOhNmasNdi07CA==

<SEC-DOCUMENT>0001424061-08-000004.txt : 20080206
<SEC-HEADER>0001424061-08-000004.hdr.sgml : 20080206
<ACCEPTANCE-DATETIME>20080206150508
ACCESSION NUMBER:		0001424061-08-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080204
FILED AS OF DATE:		20080206
DATE AS OF CHANGE:		20080206

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TRIDENT MICROSYSTEMS INC
		CENTRAL INDEX KEY:			0000859475
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				770156584
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		3408 GARRETT DRIVE
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95054-2803
		BUSINESS PHONE:		4087648808

	MAIL ADDRESS:	
		STREET 1:		3408 GARRETT DRIVE
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95054-2803

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mangan Pete J
		CENTRAL INDEX KEY:			0001424061

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20784
		FILM NUMBER:		08581218

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		408 764 8808

	MAIL ADDRESS:	
		STREET 1:		3408 GARRETT DRIVE
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95054
</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>2008-02-04</periodOfReport>

    <issuer>
        <issuerCik>0000859475</issuerCik>
        <issuerName>TRIDENT MICROSYSTEMS INC</issuerName>
        <issuerTradingSymbol>TRID</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001424061</rptOwnerCik>
            <rptOwnerName>Mangan Pete J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3408 GARRETT DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SANTA CLARA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95054</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Finance &amp; Interim CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>5.34</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-02-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>75000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-02-04</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>75000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>75000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The vesting commencement date is January 11, 2008.  The option is exercisable at the rate of 1/4th of the shares on the first annivarsary of the vesting commencement date, and the remaining portion of the option will vest with respect to 1/4th in equal yearly installments thereafter.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ David L. Teichmann, Attorney-in-Fact</signatureName>
        <signatureDate>2008-02-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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