<SEC-DOCUMENT>0001109357-18-000008.txt : 20180102
<SEC-HEADER>0001109357-18-000008.hdr.sgml : 20180102
<ACCEPTANCE-DATETIME>20180102173129
ACCESSION NUMBER:		0001109357-18-000008
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20171231
FILED AS OF DATE:		20180102
DATE AS OF CHANGE:		20180102

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LAWLESS ROBERT J
		CENTRAL INDEX KEY:			0001164638

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16169
		FILM NUMBER:		18502744

	MAIL ADDRESS:	
		STREET 1:		C/O CARPENTER TECHNOLOGY CORP
		STREET 2:		1047 NORTH PARK ROAD
		CITY:			WYOMISSING
		STATE:			PA
		ZIP:			19610

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EXELON CORP
		CENTRAL INDEX KEY:			0001109357
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC & OTHER SERVICES COMBINED [4931]
		IRS NUMBER:				232990190
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		PO BOX 805398
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60680-5398
		BUSINESS PHONE:		3123947399

	MAIL ADDRESS:	
		STREET 1:		PO BOX 805398
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60680-5398
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-12-31</periodOfReport>

    <issuer>
        <issuerCik>0001109357</issuerCik>
        <issuerName>EXELON CORP</issuerName>
        <issuerTradingSymbol>EXC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001164638</rptOwnerCik>
            <rptOwnerName>LAWLESS ROBERT J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>10 SOUTH DEARBORN STREET</rptOwnerStreet1>
            <rptOwnerStreet2>54TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60603</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock (Deferred Stock Units)</value>
            </securityTitle>
            <transactionDate>
                <value>2017-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>883</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>41.05</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>21205</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Exelon Directors' Deferred Stock Unit Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3273</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Phantom Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>42762</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>42762</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Constellation Deferred Compensation Plan for Non-employee Directors</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeTransaction>
            <securityTitle>
                <value>Deferred Compensation - Phantom Share Equivalents</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>856</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>39.41</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>856</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20475</value>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Balance includes 161 shares acquired on December 8, 2017 through automatic dividend reinvestment.</footnote>
        <footnote id="F2">Phantom stock units (which are in the form of deferred stock units) converted from the legacy Constellation Energy Group (CEG) Directors Deferred Compensation Plan to phantom units of Exelon common stock at the rate of 0.93 Exelon units for each unit of CEG. Units will be settled in cash on a 1 for 1 basis upon the termination of the reporting person's service on the Exelon board of directors. Balance updated to reflect additional stock units credited to the account through the dividend reinvestment feature of the plan.</footnote>
        <footnote id="F3">Balance includes 338 shares acquired on December 8, 2017 through automatic dividend reinvestment.</footnote>
        <footnote id="F4">Phantom share equivalents acquired through regular periodic contributions of deferred board compensation and the reinvestment of dividend equivalents in reporting person's Exelon stock fund account under multi-fund, non-qualified deferred compensation plan.  The unitized fund consists of Exelon common stock and short term investments and will be settled in cash upon the reporting person's separation from the board for any reason.  The balance of such phantom share equivalents may fluctuate from time to time due to fluctuations in the fund composition.</footnote>
        <footnote id="F5">Balance includes 148 shares equivalents accrued on November 14, 2017 through automatic dividend reinvestment.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Scott N. Peters, Esq., Attorney in Fact for Robert J. Lawless</signatureName>
        <signatureDate>2018-01-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
