<SUBMISSION>
<ACCESSION-NUMBER>0001127602-09-013502
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20090605
<FILING-DATE>20090608
<DATE-OF-FILING-DATE-CHANGE>20090608
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>JOHNS CHRISTOPHER P
<CIK>0001188488
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-12609
<FILM-NUMBER>09880515
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>ONE MARKET SPEAR TOWER STE 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>2009-06-05</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001188488</rptOwnerCik>
            <rptOwnerName>JOHNS CHRISTOPHER P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>PG&amp;E CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>ONE MARKET, SPEAR TOWER, SUITE 2400</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94105</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>SVP, and CFO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-06-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>30400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>33.02</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>72677.11</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-06-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>30400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>38.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>42277.11</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3305.12</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>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>33.02</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-06-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>30400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-01-04</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>30400</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Transaction pursuant to reporting person's Rule 10b5-1 instruction.</footnote>
        <footnote id="F2">Includes 6,077.11 Special Incentive Stock Ownership Premiums (SISOPs) (Phantom stock) awarded pursuant to the PG&amp;E Corporation Executive Stock Ownership Program, and reflects the acquisition of 66.69 SISOPs on April 15, 2009 upon conversion of dividend equivalents received on those dates.  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 of PG&amp;E Corporation common stock following termination of employment.</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 RSP balance at June 5, 2009, and reflect the acquisition of approximately 35.67 shares on April 15, 2009 due to dividend reinvestment.</footnote>
        <footnote id="F4">The option vested in four equal installments on January 3, 2006, January 3, 2007, January 3, 2008, and January 3, 2009.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Eric A. Montizambert, attorney-in-fact for Christopher P. Johns (signed Power of Attorney on file with SEC)</signatureName>
        <signatureDate>2009-06-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
