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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>0000899171-06-000042.txt : 20060518
<SEC-HEADER>0000899171-06-000042.hdr.sgml : 20060518
<ACCEPTANCE-DATETIME>20060518182259
ACCESSION NUMBER:		0000899171-06-000042
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060517
FILED AS OF DATE:		20060518
DATE AS OF CHANGE:		20060518

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROUHSELANG SANDRA M
		CENTRAL INDEX KEY:			0001227855

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-21796
		FILM NUMBER:		06853281

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		8474656000

	MAIL ADDRESS:	
		STREET 1:		1212 BROPHY
		CITY:			PARK RIDGE
		STATE:			IL
		ZIP:			60068
</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>2006-05-17</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001227855</rptOwnerCik>
            <rptOwnerName>ROUHSELANG SANDRA M</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>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice- President &amp; Controller</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock, $.01 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2006-05-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1578</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2273</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>55.40</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-05-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6465</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-05-17</value>
            </exerciseDate>
            <expirationDate>
                <value>2016-05-17</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock, $.01 par value</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>6465</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6465</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 CDW 2006 Stock Incentive Plan. The shares shall vest at a rate of 20% per year on the first five anniversaries of the date of grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Robert J. Welyki, Attorney-in-fact</signatureName>
        <signatureDate>2006-05-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
