EXHIBIT 23.1



                      [Letterhead of Deloitte & Touche LLP]

INDEPENDENT AUDITORS' CONSENT

We consent to the  incorporation by reference in this  Post-Effective  Amendment
No. 1 to Registration Statement No. 333-03040 of UnionBanCal Corporation on Form
S-3 of our report dated January 15, 2003 (which report  expresses an unqualified
opinion and includes an explanatory paragraph referring to a change in method of
accounting  for previously  recognized  goodwill and other  intangible  assets),
appearing in the Annual Report on Form 10-K/A of UnionBanCal Corporation for the
year ended December 31, 2002.

/S/ DELOITTE & TOUCHE LLP

San Francisco, California
September 30, 2003