EXHIBIT 5
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                              OPINION RE LEGALITY

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[LOGO OF GRAY CARY WARE FREIDENRICH APPEARS HERE]

ATTORNEYS AT LAW
400 HAMILTON AVENUE
PALO ALTO, CA 94301-1825
TEL (415) 328-6561
FAX (415) 327-3699


                                                                    OUR FILE NO.
                                                                  1030733-903101
                              September 6, 1995

Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C.  20549

     RE:    CUPERTINO NATIONAL BANCORP
            REGISTRATION STATEMENT ON FORM S-8 REGISTERING SHARES ISSUABLE UNDER
            THE CUPERTINO NATIONAL BANCORP 401(K) PROFIT SHARING PLAN, THE
            CUPERTINO NATIONAL BANCORP EMPLOYEE STOCK PURCHASE PLAN AND THE
            CUPERTINO NATIONAL BANCORP 1995 STOCK OPTION PLAN

Ladies and Gentlemen:

            As legal counsel for Cupertino National Bancorp, a California
corporation (the "Company"), we are rendering this opinion in connection with
the registration under the Securities Act of 1933, as amended, of up to 425,000
shares of the Common Stock, without par value, of the Company which may be
issued pursuant to the exercise of options and purchase rights granted under the
Cupertino National Bancorp 401(k) Profit Sharing Plan, the Cupertino National
Bancorp Employee Stock Purchase Plan and the Cupertino National Bancorp 1995
Stock Option Plan (the "Plans").

            We have examined all instruments, documents and records which we
deemed relevant and necessary for the basis of our opinion hereinafter
expressed. In such examination, we have assumed the genuineness of all
signatures and the authenticity of all documents submitted to us as originals
and the conformity to the originals of all documents submitted to us as copies.

            We are admitted to practice only in the State of California and we
express no opinion concerning any law other than the law of the State of
California, and the federal law of the United States.


                                       

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Securities and Exchange Commission
Page 2
 
            Based on such examination, we are of the opinion that the 425,000
 shares of Common Stock which may be issued upon exercise of options and
 purchase rights granted under the Plans are duly authorized shares of the
 Company's Common Stock, and, when issued against payment of the purchase price
 therefor in accordance with the provisions of the Plans, will be validly
 issued, fully paid and non-assessable.

            We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement referred to above and the use of our name wherever it
appears in said Registration Statement.


                                               Respectfully submitted,         
                                                                               
                                                                               
                                               /s/ Gray Cary Ware & Freidenrich
                                                                               
                                               GRAY CARY WARE & FREIDENRICH    
                                               A Professional Corporation       

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