Exhibit 5.1


August 14, 2006

San Joaquin Bancorp
1000 Truxtun Avenue
Bakersfield, CA 93301

        Re: Registration of Common Stock on Form S-8

Ladies and Gentlemen:

     We have acted as counsel for San Joaquin Bancorp, a California corporation
(the "Company"), in connection with a Registration Statement on Form S-8 (the
"Registration Statement") to be filed with the Securities and Exchange
Commission under the Securities Act of 1933 for the registration of 689,150
shares (the "Shares") of common stock, no par value per share (the "Common
Stock"), of the Company, reserved for future issuance under the San Joaquin
Bancorp Stock Option Plan and the San Joaquin Bancorp 1999 Stock Incentive Plan
(the "Plans") each of which were adopted by the Company's Board of Directors and
approved by its stockholders as of July 31, 2006.

     You have requested our opinion as to the matter set forth below in
connection with the Registration Statement. For purposes of rendering that
opinion, we have examined the Registration Statement, the Company's Articles of
Incorporation and Bylaws (the "Organizational Documents"), the Plans and the
corporate actions of the Company that provide for the adoption of the Plans and
we have made such other investigation as we have deemed appropriate. We have
examined and relied upon certificates of public officials and, as to certain
matters of fact that are material to our opinion, we have also relied on a
certificate of an officer of the Company in rendering our opinion. In rendering
our opinion, we also have made the assumptions that are customary in opinion
letters of this kind. We have not verified any of those assumptions.

     Our opinions set forth below are limited to the California General
Corporation Law, including the applicable provisions of the California
Constitution and reported judicial decisions interpreting those laws.

     Based upon and subject to the foregoing, it is our opinion that the Shares
are duly authorized for issuance by the Company and, when issued and paid for in
accordance with the terms of the applicable Plan, the Organizational Documents
and the California General Corporation Law, will be validly issued, fully paid,
and nonassessable.

     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement. In giving our consent we do not thereby admit that we



San Joaquin Bancorp
August 14, 2006
Page 2


are in the category of persons whose consent is required under Section 7 of the
1933 Act or the rules and regulations thereunder.


Very truly yours,

/s/ KIRKPATRICK & LOCKHART NICHOLSON GRAHAM LLP