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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,
 U7Ifg5ZW8r5oLksxhCmXQBh7gos1lZV6KycYvNodePAblyjlpKSJXKhdl9vLNsSo
 DFEHiUTbrlJIhCZnQZKo0Q==

<SEC-DOCUMENT>0001181431-07-035653.txt : 20070525
<SEC-HEADER>0001181431-07-035653.hdr.sgml : 20070525
<ACCEPTANCE-DATETIME>20070525163110
ACCESSION NUMBER:		0001181431-07-035653
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070523
FILED AS OF DATE:		20070525
DATE AS OF CHANGE:		20070525

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:			SHATTUCK MAYO A III
		CENTRAL INDEX KEY:			0001087426

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25931
		FILM NUMBER:		07881014

	BUSINESS ADDRESS:	
		STREET 1:		BALTIMORE GAS & ELECTRIC CO
		STREET 2:		P.O. BOX 1475
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21203
		BUSINESS PHONE:		4102345575

	MAIL ADDRESS:	
		STREET 1:		BALTIMOR GAS & ELECTRIC CO
		STREET 2:		P.O. BOX 1475
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21203
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd160089.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-05-23</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001087426</rptOwnerCik>
            <rptOwnerName>SHATTUCK MAYO A III</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>750 E. PRATT STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BALTIMORE</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>21202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman, Pres. &amp; CEO CEG</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-05-23</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>93.6153</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>491954</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>782.3965</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k) Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sale reported on this Form 4 was effected pursuant to Rule 10b5-1 trading plans.  Additional sales are scheduled to occur quarterly over the next six months pursuant to these trading plans, not to exceed an additional 150,000 shares in total.</footnote>
        <footnote id="F2">This amount includes shares obtained through reinvested dividends.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Mayo A. Shattuck III</signatureName>
        <signatureDate>2007-05-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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