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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 RrT6dNg8HGqZ2CuOm8mgT5BTs0eQCrXdYOTFVHDc8+JNsgXOARyNwpicOnbRYIEt
 VyvHuCXsDFVJtOqxJwq0tg==

<SEC-DOCUMENT>0001004440-04-000046.txt : 20040504
<SEC-HEADER>0001004440-04-000046.hdr.sgml : 20040504
<ACCEPTANCE-DATETIME>20040504124840
ACCESSION NUMBER:		0001004440-04-000046
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040501
FILED AS OF DATE:		20040504

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CONSTELLATION ENERGY GROUP INC
		CENTRAL INDEX KEY:			0001004440
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC SERVICES [4911]
		IRS NUMBER:				521964611
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		750 E PRATT ST
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21202
		BUSINESS PHONE:		4107832800

	MAIL ADDRESS:	
		STREET 1:		750 E PRATT STREET
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21202

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CONSTELLATION ENERGY CORP
		DATE OF NAME CHANGE:	19951220

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	RH ACQUISITION CORP
		DATE OF NAME CHANGE:	19951205

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			UGOL MARC L
		CENTRAL INDEX KEY:			0001088865
		STANDARD INDUSTRIAL CLASSIFICATION:	TELEPHONE & TELEGRAPH APPARATUS [3661]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0101

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25931
		FILM NUMBER:		04776516

	BUSINESS ADDRESS:	
		STREET 1:		TELLABS OPERATIONS INC
		STREET 2:		4951 INDIANA AVENUE
		CITY:			LISLE
		STATE:			IL
		ZIP:			60532
		BUSINESS PHONE:		6303788800

	MAIL ADDRESS:	
		STREET 1:		4951 INDIANA AVE
		STREET 2:		C/O TELLABS OPERATIONS INC
		CITY:			LISLE
		STATE:			IL
		ZIP:			60532
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>c0001088865d20040504f4f.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-05-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001004440</issuerCik>
        <issuerName>CONSTELLATION ENERGY GROUP INC</issuerName>
        <issuerTradingSymbol>CEG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001088865</rptOwnerCik>
            <rptOwnerName>UGOL MARC L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>750 E. PRATT ST.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BALTIMORE</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>21202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. VP-HR CEG</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-05-01</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1006</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>38.575</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12412.595</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Shares of performance-based restricted stock granted on 5/2/03 and 2/26/04 have vested and shares were withheld to pay the taxes due.</footnote>
        <footnote id="F2">This amount includes shares obtained through reinvested dividends.  In addition, Mr. Ugol owns indirectly 254.302 shares of common stock by a 401(k) Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Marc L. Ugol</signatureName>
        <signatureDate>2004-05-04</signatureDate>
    </ownerSignature>
</ownershipDocument>

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