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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 lY/cMPHvlS0QvF2jAQJs2Q==

<SEC-DOCUMENT>0000043704-06-000038.txt : 20060525
<SEC-HEADER>0000043704-06-000038.hdr.sgml : 20060525
<ACCEPTANCE-DATETIME>20060525103508
ACCESSION NUMBER:		0000043704-06-000038
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060523
FILED AS OF DATE:		20060525
DATE AS OF CHANGE:		20060525

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GREEN MOUNTAIN POWER CORP
		CENTRAL INDEX KEY:			0000043704
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC SERVICES [4911]
		IRS NUMBER:				030127430
		STATE OF INCORPORATION:			VT
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		163 ACORN LANE
		STREET 2:		.
		CITY:			COLCHESTER
		STATE:			VT
		ZIP:			05446
		BUSINESS PHONE:		8028645731

	MAIL ADDRESS:	
		STREET 1:		163 ACORN LANE
		STREET 2:		.
		CITY:			COLCHESTER
		STATE:			VT
		ZIP:			05446

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GRIFFIN ROBERT J
		CENTRAL INDEX KEY:			0001247228

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08291
		FILM NUMBER:		06865894

	MAIL ADDRESS:	
		STREET 1:		GREEN MOUNTAIN POWER CORP
		STREET 2:		163 ACORN LANE
		CITY:			COLCHESTER
		STATE:			VT
		ZIP:			05446
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-05-23</periodOfReport>

    <issuer>
        <issuerCik>0000043704</issuerCik>
        <issuerName>GREEN MOUNTAIN POWER CORP</issuerName>
        <issuerTradingSymbol>GMP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001247228</rptOwnerCik>
            <rptOwnerName>GRIFFIN ROBERT J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>163 ACORN LANE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>COLCHESTER</rptOwnerCity>
            <rptOwnerState>VT</rptOwnerState>
            <rptOwnerZipCode>05446</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-05-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3403</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9784.6192</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-05-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>348</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>28.64</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9436.6192</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12181.992</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k)</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>513</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Custodian for Sons</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F4">Includes 116.7736 shares acquired between February 16, 2006 and May 23, 2006 under the GMP 401(k) plan.  The information in this report is based on a plan statement as of May 23, 2006.</footnote>
        <footnote id="F3">Disposition represents withholding of common shares to satisfy tax withholding oblgiations associated with the vesting of stock units granted on May 27, 2005.</footnote>
        <footnote id="F2">Includes 1362.5284 shares acquired between February 16, 2006 and May 23, 2006 under the GMP Dividend Reinvestment Plan.  The information in this report is based on a plan statement as of May 23, 2006.</footnote>
        <footnote id="F1">Shares represent stock units that will be payable on a one-for-one basis in shares of common stock at vesting.  50 percent of the stock units will vest on May 22, 2007 and the remaining 50 percent of the stock units will vest on May 22, 2008.  The vesting dates are subject to deferral at the election of the reporting person.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Donald J. Rendall, Attorney-In-Fact</signatureName>
        <signatureDate>2006-05-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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