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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 MBRmSg+/iWvqO60y/5Q20S2mm5ZX0u+Iex8reUpDeRxfrb83yauKVZUMRYiGC/Pc
 x9sfkiOwTaVoAewFS/rZHw==

<SEC-DOCUMENT>0000899171-04-000109.txt : 20041112
<SEC-HEADER>0000899171-04-000109.hdr.sgml : 20041111
<ACCEPTANCE-DATETIME>20041112122225
ACCESSION NUMBER:		0000899171-04-000109
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041110
FILED AS OF DATE:		20041112
DATE AS OF CHANGE:		20041112

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			JAMES STEPHAN A
		CENTRAL INDEX KEY:			0001232907

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-21796
		FILM NUMBER:		041137263

	MAIL ADDRESS:	
		STREET 1:		C/O ACCENTURE LEGAL & COMMERICAL GROUP
		STREET 2:		23RD FL 161 N CLARK STREET
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60601

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CDW CORP
		CENTRAL INDEX KEY:			0000899171
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-CATALOG & MAIL-ORDER HOUSES [5961]
		IRS NUMBER:				363310735
		STATE OF INCORPORATION:			IL
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		200 N MILWAUKEE AVE
		CITY:			VERNON HILLS
		STATE:			IL
		ZIP:			60061
		BUSINESS PHONE:		8474656000

	MAIL ADDRESS:	
		STREET 1:		200 N MILWAUKEE AVE
		CITY:			VERNON HILLS
		STATE:			IL
		ZIP:			60061

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CDW COMPUTER CENTERS INC
		DATE OF NAME CHANGE:	19930322
</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>2004-11-10</periodOfReport>

    <issuer>
        <issuerCik>0000899171</issuerCik>
        <issuerName>CDW CORP</issuerName>
        <issuerTradingSymbol>CDWC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001232907</rptOwnerCik>
            <rptOwnerName>JAMES STEPHAN A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 NORTH  MILWAUKEE AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>VERNON HILLS</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60061</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock, $.01 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2004-11-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options (Right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>62.43</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-11-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2478</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-11-10</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-11-10</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock, $.01 par value</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2478</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2478</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The shares were awarded pursuant to a Restricted Stock Award under the 2004 Non-Employee Director Equity Compensation Plan. The shares shall vest on the fifth anniversary of the date of grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Stephan A. James</signatureName>
        <signatureDate>2004-11-11</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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