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                                                                     EXHIBIT 5.1


                   [BOND, SCHOENECK & KING, LLP LETTERHEAD]


July 3, 2000

Community Bank System, Inc.
5790 Widewaters Parkway
DeWitt, New York 13214-1883

Re:    Community Bank System, Inc. / Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as counsel to Community Bank System, Inc., a Delaware corporation
(the "Company"), in connection with the preparation and filing of a registration
statement on Form S-3 (the "Registration Statement") under the Securities Act of
1933, as amended (the "Securities Act"), covering an aggregate of 300,000 shares
of common stock, no par value, of the Company (the "Shares").

As such counsel, we have examined such corporate records, certificates and other
documents and such questions of law as we have considered necessary or
appropriate for the purposes of this opinion. In rendering this opinion, we have
(a) assumed (i) the genuineness of all signatures on all documents examined by
us, (ii) the authenticity of all documents submitted to us as originals, and
(iii) the conformity to original documents of all documents submitted to us as
photostatic or conformed copies and the authenticity of the originals of such
copies; and (b) relied on (i) certificates of public officials and (ii) as to
matters of fact, statements and certificates of officers of the Company.

Based upon the foregoing, we are of the opinion that the Shares have been
validly authorized and issued, and are fully paid and non-assessable shares of
common stock of the Company.

We are attorneys admitted to the Bar of the State of New York, and we express no
opinion as to the laws of any jurisdiction other than the laws of the United
States of America and the State of Delaware.

We consent to the filing of this opinion as an exhibit to the Registration
Statement and to the use of our name under the heading "Legal Matters" in the
prospectus forming a part of the Registration Statement. In giving such consent
we do not thereby concede that we are within the category of persons whose
consent is required under Section 7 of the Securities Act or the rules and
regulations promulgated thereunder.



/s/ BOND, SCHOENECK & KING, LLP