UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 9, 2010

UnionBanCal Corporation

(Exact name of registrant as specified in its charter)

400 California Street

San Francisco, CA  94104-1302

(Address of principal executive offices) (Zip Code)

Tel. (415) 765-2969

Registrant’s telephone number, including area code

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01.              Regulation FD Disclosure.

On December 9, 2010, Union Bank, N.A. (the “Bank”), the wholly-owned bank subsidiary of UnionBanCal Corporation (the “Company”), proposed, subject to market conditions, to issue an undetermined aggregate amount of 3-year senior bank notes, the terms of which are described in the preliminary pricing supplement relating to the Bank’s bank note program, which is furnished herewith as Exhibit 99.1 and is incorporated by reference herein.

The information furnished pursuant to this Item 7.01, including Exhibit 99.1, shall not be deemed to be “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, and shall not be deemed to constitute an admission that such information or exhibit is required to be furnished pursuant to Regulation FD or that such information or exhibit contains material information that is not otherwise publicly available. In addition, the Company does not assume any obligation to update such information or exhibit in the future.

This Current Report on Form 8-K may include certain “forward-looking statements” about the Company and the Bank.  These forward-looking statements are based on management’s current expectations and are subject to certain risks, uncertainties and changes in circumstances.  Actual results may differ materially from these expectations due to changes in global political, economic, business, competitive, market and regulatory factors. More detailed information about these risk factors is contained in the Company’s most recent reports filed with the Securities and Exchange Commission on Forms 10-K, 10-Q and 8-K, each as it may be amended from time to time, which identify important risk factors that could cause actual results to differ materially from those contained in the forward-looking statements.  The Company and the Bank undertake no obligation to update these forward-looking statements to reflect events or circumstances arising after the date on which they are made.

Item 9.01.              Financial Statements and Exhibits.

(d)           Exhibits.

99.1         Preliminary Pricing Supplement

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date:  December 9, 2010

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EXHIBIT INDEX

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