Exhibit 5.1

                              Opinion Re: Legality




                                ----------------
                                    LILLICK
                                --------&-------
                                    CHARLES
                                ----------------
                                      LLP
                                ATTORNEYS AT LAW

Two Embarcadero Center                                       Phone: 415-984-8200
San Francisco, CA 94111-3996                             Fascimile: 415-984-8300

                                December 20, 1999

Writer's Email Address                               Writer's Direct Dail Number
rfaye@lillick.com                                            415-984-8365


North Bay Bancorp
1500 Soscol Avenue
Napa, California 94559

Ladies and Gentlemen:

         With  reference  to the  Registration  Statement  on Form SB-2 filed by
North Bay Bancorp  ("North Bay") with the Securities and Exchange  Commission in
connection with the  registration  under the Securities Act of 1933, as amended,
of shares of North Bay Common Stock,  no par value,  (the "Shares") to be issued
in connection with the public sale of the Shares by North Bay:

         We are of the opinion  that the Shares have been duly  authorized  and,
when issued in  accordance  with the  Prospectus  contained in the  Registration
Statement, will be validly issued, fully paid and nonassessable.

         We hereby  consent to the filing of this  opinion as Exhibit 5.1 to the
Registration  Statement,  and any  amendments  thereto,  and the use of our name
under  the  caption  "Legal  Matters"  in the  Registration  Statement,  and any
amendments thererto, and in the Prospectus included therein.

                                                  Very truly yours,


                                                  /s/ Lillick & Charles LLP

                                                  LILLICK & CHARLES LLP