-----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,
 BL33u+TX3OU1EtFsiKOhv0ONuYVEmAYDA7M+teiUFDq15hu8+bwbGddY8oaje2Mw
 46VEWMEUot0hAN5M6Y73NQ==

<SEC-DOCUMENT>0000107815-04-000056.txt : 20040126
<SEC-HEADER>0000107815-04-000056.hdr.sgml : 20040126
<ACCEPTANCE-DATETIME>20040126183313
ACCESSION NUMBER:		0000107815-04-000056
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040102
FILED AS OF DATE:		20040126

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 2949
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53201
		BUSINESS PHONE:		4142212345

	MAIL ADDRESS:	
		STREET 1:		231 WEST MICHIGAN STREET
		STREET 2:		P O BOX 2949
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53201

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DAVIS WILLIE D
		CENTRAL INDEX KEY:			0001053288

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09057
		FILM NUMBER:		04544362

	BUSINESS ADDRESS:	
		STREET 1:		BASSETT FURNITURE INDUSTRIES INC
		STREET 2:		P O BOX 626
		CITY:			BASSETT
		STATE:			VA
		ZIP:			24055
		BUSINESS PHONE:		5406296209

	MAIL ADDRESS:	
		STREET 1:		BASSETT FURNITURE INDUSTRIES INC
		STREET 2:		P O BOX 626
		CITY:			BASSETT
		STATE:			VA
		ZIP:			24055
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>c0001053288d20040126f4af.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2004-01-02</periodOfReport>

    <dateOfOriginalSubmission>2004-01-06</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001053288</rptOwnerCik>
            <rptOwnerName>DAVIS WILLIE D</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>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-01-02</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1945</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11086</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person filed a Form 4 on January 6, 2004 which inadvertently overstated his total holdings.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Kristine A. Rappe as Attorney-in-Fact</signatureName>
        <signatureDate>2004-01-26</signatureDate>
    </ownerSignature>
</ownershipDocument>

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