<SUBMISSION>
<ACCESSION-NUMBER>0001127602-09-000642
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20090102
<FILING-DATE>20090106
<DATE-OF-FILING-DATE-CHANGE>20090106
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>SIMON JOHN R
<CIK>0001199412
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-12609
<FILM-NUMBER>09509053
</FILING-VALUES>
<BUSINESS-ADDRESS>
<PHONE>415.267.7000
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>ONE MARKET, SPEAR TOWER, SUITE 2400
<CITY>SAN FRANCISCO
<STATE>CA
<ZIP>94105
</MAIL-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>PG&E CORP
<CIK>0001004980
<ASSIGNED-SIC>4931
<IRS-NUMBER>943234914
<STATE-OF-INCORPORATION>CA
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>ONE MARKET SPEAR TOWER
<STREET2>SUITE 2400
<CITY>SAN FRANCISCO
<STATE>CA
<ZIP>94105
<PHONE>4152677000
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>ONE MARKET SPEAR TOWER
<STREET2>SUITE 2400
<CITY>SAN FRANCISCO
<STATE>CA
<ZIP>94105
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>PG&E PARENT CO INC
<DATE-CHANGED>19951214
</FORMER-COMPANY>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-01-02</periodOfReport>

    <issuer>
        <issuerCik>0001004980</issuerCik>
        <issuerName>PG&amp;E CORP</issuerName>
        <issuerTradingSymbol>PCG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001199412</rptOwnerCik>
            <rptOwnerName>SIMON JOHN R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>PG&amp;E CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>ONE MARKET, SPEAR TOWER, SUITE 2400</rptOwnerStreet2>
            <rptOwnerCity></rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode>94105</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>SVP-Human Resources</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-01-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>432</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>38.81</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8705</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-01-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>17.39</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8722.39</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>90.63</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Held by Trustee of PG&amp;E Corporation Retirement Savings Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents Special Incentive Stock Ownership Premiums (SISOPs) (phantom stock) awarded pursuant to the PG&amp;E Corporation Executive Stock Ownership Program.  SISOPs vest three years after the date of grant subject to accelerated vesting upon certain events.  Unvested SISOPs are subject to forfeiture if certain stock ownership targets are not met.  Vested SISOPs are automatically payable in an equal number of shares following termination of employment.</footnote>
        <footnote id="F2">Includes 17.39 SISOPs pursuant to the PG&amp;E Corporation Executive Stock Ownership Program.</footnote>
        <footnote id="F3">Represents the approximate number of shares of PG&amp;E Corporation common stock held for the reporting person in the PG&amp;E Corporation Stock Fund of the PG&amp;E Corporation Retirement Savings Plan (RSP).  That fund holds units consisting of PG&amp;E Corporation common stock and a small short-term investments component.  The number of shares is computed by dividing the value of the units by the daily closing price.  Dividends are automatically invested in additional units at the election of the participant.  These holdings have been trued up to conform to the RSP balance as of January 2, 2009, and reflect the acquisition of approximately 0.47 shares on July 15, 2008, and 1.11 shares on October 15, 2008 due to dividend reinvestment.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Eileen O. Chan, attorney-in-fact for John R. Simon (signed Power of Attorney on file with SEC)</signatureName>
        <signatureDate>2009-01-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
