-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 LLGtK5O82IFKEKLIk1Gs+WDGPmTLy1QRx+e8zjsMip7VlS5NuyUcrPYeCZGUU016
 5jLa5gjDJEoslHFv6Stn8A==

<SEC-DOCUMENT>0001239944-04-000125.txt : 20040909
<SEC-HEADER>0001239944-04-000125.hdr.sgml : 20040909
<ACCEPTANCE-DATETIME>20040909160955
ACCESSION NUMBER:		0001239944-04-000125
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040907
FILED AS OF DATE:		20040909
DATE AS OF CHANGE:		20040909

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ACE BRIAN R
		CENTRAL INDEX KEY:			0001264817

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13695
		FILM NUMBER:		041023087

	BUSINESS ADDRESS:	
		STREET 1:		2 PINE PLACE
		CITY:			TUNKHANNOCK
		STATE:			PA
		ZIP:			18657
		BUSINESS PHONE:		5708335832

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COMMUNITY BANK SYSTEM INC
		CENTRAL INDEX KEY:			0000723188
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		IRS NUMBER:				161213679
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		5790 WIDEWATERS PKWY
		CITY:			DEWITT
		STATE:			NY
		ZIP:			13214
		BUSINESS PHONE:		8007242262

	MAIL ADDRESS:	
		STREET 1:		5790 WIDEWATERS PARKWAY
		CITY:			DEWITT
		STATE:			NY
		ZIP:			13214
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-09-07</periodOfReport>

    <issuer>
        <issuerCik>0000723188</issuerCik>
        <issuerName>COMMUNITY BANK SYSTEM INC</issuerName>
        <issuerTradingSymbol>CBU</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001264817</rptOwnerCik>
            <rptOwnerName>ACE BRIAN R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>R.R. #1, BOX 1550</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LACEYVILLE</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>18623</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>
            </securityTitle>
            <transactionDate>
                <value>2004-09-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7712</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.6453</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>32014</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.6453</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-09-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7712</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.6452</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2003-11-21</value>
            </exerciseDate>
            <expirationDate>
                <value>2006-01-02</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7712</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7712</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On April 12, 2004, the common stock of Community Bank System, Inc. split 2-for-1, resulting in the reporting person's acquisition of 12,151 additional shares of common stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Donna J. Drengel, as attorney-in-fact, pursuant to a power of attorney</signatureName>
        <signatureDate>2004-09-09</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----