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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 A8RnzgdmXnEnDZDRgT3LZquEheQa8DY8qLFLBcxztpu60ip3ClhhxRjFkVfAeRbJ
 +WAJ05Q9u5IeNbhz+PO4tQ==

<SEC-DOCUMENT>0000024751-10-000119.txt : 20100903
<SEC-HEADER>0000024751-10-000119.hdr.sgml : 20100903
<ACCEPTANCE-DATETIME>20100903164337
ACCESSION NUMBER:		0000024751-10-000119
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100901
FILED AS OF DATE:		20100903
DATE AS OF CHANGE:		20100903

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GERMAN MICHAEL I
		CENTRAL INDEX KEY:			0001012714

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-00643
		FILM NUMBER:		101058100

	MAIL ADDRESS:	
		STREET 1:		C/O ENERGY EAST CORP
		STREET 2:		PO BOX 3287
		CITY:			ITHACA
		STATE:			NY
		ZIP:			14852-3287

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CORNING NATURAL GAS CORP
		CENTRAL INDEX KEY:			0000024751
		STANDARD INDUSTRIAL CLASSIFICATION:	NATURAL GAS TRANSMISSION & DISTRIBUTION [4923]
		IRS NUMBER:				160397420
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		330 W WILLIAM ST
		STREET 2:		P O BOX 58
		CITY:			CORNING
		STATE:			NY
		ZIP:			14830
		BUSINESS PHONE:		6079363755

	MAIL ADDRESS:	
		STREET 1:		330 W WILLIAM STREET
		STREET 2:		P O BOX 58
		CITY:			CORNING
		STATE:			NY
		ZIP:			14830
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-09-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000024751</issuerCik>
        <issuerName>CORNING NATURAL GAS CORP</issuerName>
        <issuerTradingSymbol>CNIG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001012714</rptOwnerCik>
            <rptOwnerName>GERMAN MICHAEL I</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>330 WEST WILLIAM STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CORNING</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>14830</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-09-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>X</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>16509</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>18</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>219757</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote (1)</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Common Stock Subscription (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>18</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-09-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>X</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>16509</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2010-07-19</value>
            </exerciseDate>
            <expirationDate>
                <value>2010-08-27</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>16509</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote (2)</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">19,353 shares of common stock are owned jointly by Mr. German and two other individuals and 5,107 shares are owned by Mr. German's son. Mr. German disclaims these shares of common stock except to the extent of his percuniary interest therein. Total includes 756 shares acquired by Mr. German through the Issuer's Dividend Reinvestment Program.</footnote>
        <footnote id="F2">Includes 1,746 subscription rights owned jointly by Mr. German and two other individuals and 939 subscription rights owned by Mr. German's son. Mr. German disclaims these rights except to the extent of his percuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Michael I. German</signatureName>
        <signatureDate>2010-09-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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