-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 IpfaSMwDQDtqlk5wfSzwKoPWfCrOtWfs2sc4muLh7vzOMKL16OiKCHAQqs8zCtRD
 zCaGeQZie8vzv7eWMprvFQ==

<SEC-DOCUMENT>0000107815-09-000053.txt : 20090910
<SEC-HEADER>0000107815-09-000053.hdr.sgml : 20090910
<ACCEPTANCE-DATETIME>20090910160702
ACCESSION NUMBER:		0000107815-09-000053
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090908
FILED AS OF DATE:		20090910
DATE AS OF CHANGE:		20090910

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BOWLES BARBARA L
		CENTRAL INDEX KEY:			0001034439
		STATE OF INCORPORATION:			TN
		FISCAL YEAR END:			0131

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09057
		FILM NUMBER:		091062935

	MAIL ADDRESS:	
		STREET 1:		100 MISSION RIDGE
		STREET 2:		C/O DOLLAR GENERAL CORP
		CITY:			GOODLETTSVILLE
		STATE:			TN
		ZIP:			37072

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WISCONSIN ENERGY CORP
		CENTRAL INDEX KEY:			0000783325
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC & OTHER SERVICES COMBINED [4931]
		IRS NUMBER:				391391525
		STATE OF INCORPORATION:			WI
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		231 W MICHIGAN ST
		STREET 2:		P O BOX 1331
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53201
		BUSINESS PHONE:		414-221-2345

	MAIL ADDRESS:	
		STREET 1:		231 WEST MICHIGAN STREET
		STREET 2:		P O BOX 1331
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53201
</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>2009-09-08</periodOfReport>

    <issuer>
        <issuerCik>0000783325</issuerCik>
        <issuerName>WISCONSIN ENERGY CORP</issuerName>
        <issuerTradingSymbol>WEC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001034439</rptOwnerCik>
            <rptOwnerName>BOWLES BARBARA L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>231 WEST MICHIGAN STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILWAUKEE,</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53203</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-09-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>8.3546</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>44.885</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>8.3546</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>27.8996</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">One-for-one.</footnote>
        <footnote id="F2">These phantom stock units were acquired pursuant to a deferral of director fees in an acquisition exempt from Section 16(b) pursuant to Rule 16b-3(d)</footnote>
        <footnote id="F3">These phantom stock units were accrued under the WEC Directors' Deferred Compensation Plan (&quot;DDCP&quot;) and are to be settled in cash following the reporting person's termination of service as a director.</footnote>
        <footnote id="F4">Includes phantom stock units accrued pursuant to a dividend reinvestment feature of the DDCP in transactions exempt from Section 16 pursuant to Rule 16a-11.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Joshua M. Erickson, as Attorney-in-Fact</signatureName>
        <signatureDate>2009-09-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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