<SEC-DOCUMENT>0001127602-18-009548.txt : 20180302
<SEC-HEADER>0001127602-18-009548.hdr.sgml : 20180302
<ACCEPTANCE-DATETIME>20180302125511
ACCESSION NUMBER:		0001127602-18-009548
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180228
FILED AS OF DATE:		20180302
DATE AS OF CHANGE:		20180302

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Strah Steven E
		CENTRAL INDEX KEY:			0001348488

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	333-21011
		FILM NUMBER:		18660856

	MAIL ADDRESS:	
		STREET 1:		76 SOUTH MAIN STREET
		CITY:			AKRON
		STATE:			OH
		ZIP:			44308

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FIRSTENERGY CORP
		CENTRAL INDEX KEY:			0001031296
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC SERVICES [4911]
		IRS NUMBER:				341843785
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		76 SOUTH MAIN ST
		CITY:			AKRON
		STATE:			OH
		ZIP:			44308-1890
		BUSINESS PHONE:		330-761-7837

	MAIL ADDRESS:	
		STREET 1:		76 SOUTH MAIN ST
		CITY:			AKRON
		STATE:			OH
		ZIP:			44308-1890
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-02-28</periodOfReport>

    <issuer>
        <issuerCik>0001031296</issuerCik>
        <issuerName>FIRSTENERGY CORP</issuerName>
        <issuerTradingSymbol>FE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001348488</rptOwnerCik>
            <rptOwnerName>Strah Steven E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>76 S. MAIN ST.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>AKRON</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44308</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>Sr VP &amp; President FE Utilities</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom 3/18D</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-02-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>6601.132</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>32.24</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>6601.132</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6601.132</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">1 for 1</footnote>
        <footnote id="F2">Each share of phantom stock is the economic equivalent of one share of FirstEnergy Corp. common stock.?The phantom stock represents a portion of a Short-Term Incentive Program award earned on February 20, 2018 and deferred under the FirstEnergy Corp. Amended and Restated Executive Deferred Compensation Plan, which becomes payable in cash upon retirement or other termination of employment.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Jennifer L. Geyer, attorney-in-fact</signatureName>
        <signatureDate>2018-03-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
