-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 H8ROO0640uk6lnL5DW95EXAS9op8GAWpU2ttisK1l2eGdEaU6P+wiEcXAShdkFeD
 vbQmVzyT/se4/59DPUDk2A==

<SEC-DOCUMENT>0000070145-10-000008.txt : 20100106
<SEC-HEADER>0000070145-10-000008.hdr.sgml : 20100106
<ACCEPTANCE-DATETIME>20100106084319
ACCESSION NUMBER:		0000070145-10-000008
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100104
FILED AS OF DATE:		20100106
DATE AS OF CHANGE:		20100106

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SALERNO FREDERIC V
		CENTRAL INDEX KEY:			0001180138

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-03880
		FILM NUMBER:		10509923

	MAIL ADDRESS:	
		STREET 1:		115 S JEFFERSON RD
		CITY:			WHIPPANY
		STATE:			NJ
		ZIP:			07981

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NATIONAL FUEL GAS CO
		CENTRAL INDEX KEY:			0000070145
		STANDARD INDUSTRIAL CLASSIFICATION:	NATURAL GAS DISTRIBUTION [4924]
		IRS NUMBER:				131086010
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		6363 MAIN STREET
		CITY:			WILLIAMSVILLE
		STATE:			NY
		ZIP:			14221-5887
		BUSINESS PHONE:		716-857-7000

	MAIL ADDRESS:	
		STREET 1:		6363 MAIN STREET
		STREET 2:		6363 MAIN STREET
		CITY:			WILLIAMSVILLE
		STATE:			NY
		ZIP:			14221-5887
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-01-04</periodOfReport>

    <issuer>
        <issuerCik>0000070145</issuerCik>
        <issuerName>NATIONAL FUEL GAS CO</issuerName>
        <issuerTradingSymbol>NFG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001180138</rptOwnerCik>
            <rptOwnerName>SALERNO FREDERIC V</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>8 COMMODORE AVE.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>RYE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10580</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2010-01-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>50.59</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>965</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Acquired through quarterly grant under the National Fuel Gas Company Retainer Policy for Non-Employee Directors.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>J. R. Peterson, Attorney in Fact</signatureName>
        <signatureDate>2010-01-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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