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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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 rWY31be9PPbEctA3Z7yUBQ==

<SEC-DOCUMENT>0000024751-10-000109.txt : 20100826
<SEC-HEADER>0000024751-10-000109.hdr.sgml : 20100826
<ACCEPTANCE-DATETIME>20100826140247
ACCESSION NUMBER:		0000024751-10-000109
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100825
FILED AS OF DATE:		20100826
DATE AS OF CHANGE:		20100826

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:		101040052

	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>2010-08-25</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 and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-08-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>X</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3901</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>18</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>203226</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</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>18</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-08-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>X</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3901</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>3901</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15993</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">17,350 shares of common stock are owned jointly by Mr. German and two other individuals and 4,168 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 757 shares acquired by Mr. German through the Issuer's Dividend Reinvestment Program.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Michael I. German</signatureName>
        <signatureDate>2010-08-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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