<PAGE>


As filed with the Securities and Exchange Commission on January 27, 2000


                SECURITIES AND EXCHANGE COMMISSION
                       Washington, DC  20549

                       ---------------------

                             FORM S-8
                      REGISTRATION STATEMENT
                              UNDER
                    THE SECURITIES ACT OF 1933

                       ---------------------

                       UNIONBANCAL CORPORATION
        (Exact name of registrant as specified in its charter)

          California                               94-1234979
  (State or other jurisdiction                  (I.R.S. Employer
  of incorporation or organization)            Identification No.)

     400 California Street
       San Francisco, CA                             94104
(Address of principal executive offices)           (Zip Code)

    YEAR 2000 UNIONBANCAL CORPORATION MANAGEMENT STOCK PLAN
                     (Full title of the Plan)

                    JOHN H. MCGUCKIN, JR., ESQ.
           Executive Vice President and General Counsel

                        UNIONBANCAL CORPORATION
                         400 California Street
                        San Francisco, CA 94104
                            (415) 765-2969

       (name, address, including zip code and telephone number,
               including area code, of agent for service)


                    CALCULATION OF REGISTRATION FEE


<TABLE>
<CAPTION>

                                        PROPOSED MAXIMUM    PROPOSED MAXIMUM
TITLE OF SECURITIES     AMOUNT TO BE    OFFERING PRICE        AGGREGATE          AMOUNT OF
TO BE REGISTERED         REGISTERED       PER SHARE          OFFERING PRICE    REGISTRATION FEE
-------------------     ------------    -----------------   -----------------  -----------------
<S>                     <C>             <C>                 <C>                <C>
Common Stock,           10,000,000(1)   $32.3125(2)         $323,125,000(2)    $85,305
no par value

</TABLE>

(1) Estimated maximum aggregate number of shares of UnionBanCal Corporation
    Common Stock that may be awarded and/or sold pursuant to the Plan.

(2) Estimated solely for the purpose of computing the registration fee pursuant
    to Rule 457(c) on the basis of the average high and low prices for the
    Common Stock on January 24, 2000 as reported on the New York Stock Exchange.

<PAGE>

                                         PART I

                  INFORMATION REQUIRED IN THE SECTION 10 (a) PROSPECTUS

ITEM 1. PLAN INFORMATION.

      The document(s) containing the information specified in Item 1 will be
sent or given to participants in the Year 2000 UnionBanCal Corporation
Management Stock Plan (the "Plan") as specified in Rule 428(b)(1) and is not
required to be filed as part of the registration statement.

ITEM 2. REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION.

      The document(s) containing the information specified in Item 2 will be
sent or given to participants in the Plan as specified in Rule 428(b)(1) and
is not required to be filed as part of this registration statement.

                                         PART II

                     INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

This Registration Statement covers shares of Common Stock of UnionBanCal
Corporation (the "Registrant") that have been authorized for issuance
pursuant to the Registrant's Plan.

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

      There are hereby incorporated by reference in this Registration
Statement the following documents and information heretofore filed with the
Commission.

    (a) The Registrant's Annual Report filed on Form 10-K
        for the fiscal year ended December 31, 1998.

    (b) The Registrant's proxy statement in connection with the Annual
        Meeting of Shareholders of Common Stock of the Registrant held
        on May 26, 1999.

    (c) All other reports filed pursuant to Section 13(a) or 15(d) of the
        Exchange Act since the end of the fiscal year covered by the
        Registrant's Annual Report on Form 10-K referred to in (a) above.

    (d) The description of the Registrant's Common Stock, no par value,
        contained in the Registrant's Registration Statement on Form 8-A,
        dated June 7, 1999, filed pursuant to Section 12(g) of the Securities
        Exchange Act of 1934, as amended (the "Exchange Act").


    All documents filed by the Registrant subsequently pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act before the filing of a
post-effective amendment which indicates that all securities offered hereby
have been sold or which deregisters all securities then remaining unsold,
shall be deemed to be incorporated by reference in this Registration
Statement and to be a part hereof from the date of filing of such documents.

ITEM 4. DESCRIPTION OF SECURITIES.

      Not applicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

      Not applicable.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

      Sections 204 (a) and 317 of the California General Corporation Law
("CCGL") authorize a corporation to indemnify its directors and officers
against certain liabilities and to eliminate their liability to the
corporation except in certain circumstances.  The Registrant's Amended and
Restated Articles of Incorporation contain a provision

                                       2
<PAGE>


limiting the liability of the Registrant's directors for monetary damages to
the fullest extent permitted by California law. The Registrant's Amended and
Restated Articles of Incorporation contain a provision pursuant to which the
Registrant is authorized to indemnify its directors, officers, employees and
other agents through Bylaw provisions in excess to the indemnification
permitted by Section 317 of the CCGL subject only to the applicable limits as
set forth in Section 204 of the CCGL.

      In addition, the Registrant's Bylaws contain a provision limiting the
liability of the Registrant's directors for monetary damages to the fullest
extent permitted by California law and providing for indemnification to its
directors, officers, employees and other agents.  Moreover, under California
law each director is subject to liability for breach of the director's duty
of loyalty to the Company, for acts or omissions involving intentional
misconduct or knowing and culpable violations of law, for acts or omissions
that the director believes to be contrary to the best interest of the Company
or its shareholders or that involve the absence of good faith on the part of
the director, for any transaction from which the director derived an improper
personal benefit, for acts or omissions involving a reckless disregard for
the director's duty to the Registrant or its shareholders when the director
was aware or should have been aware of a risk of serious injury to the
Registrant or its shareholders, for acts or omissions that constitute an
unexcused pattern of inattention that amount to an abdication of the
director's duty to the Registrant or its shareholders, for improper
transactions between the director and the Registrant, for improper
distributions to shareholders, and for loans to officers and directors.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED.

      Not applicable.

ITEM 8. EXHIBITS.

<TABLE>
<CAPTION>

REGULATION S-K                                              REFERENCE TO PRIOR FILING OR
EXHIBIT NO.       DESCRIPTION                               EXHIBIT NO. ATTACHED HERETO
--------------    -----------                               ----------------------------
<C>               <S>                                       <C>
 4.1              Year 2000 UnionBanCal Corporation         Filed as Exhibit A to Registrant's proxy
                  Management Stock Plan                     statement in connection with the Annual
                                                            Meeting of Shareholders of Common
                                                            Stock of the Registrant held on May 26,
                                                            1999 and filed with the SEC on April 29,
                                                            1999 under file number 333-03040 and
                                                            incorporated by reference herein.

 5.1              Opinion of Graham & James LLP             Attached as Exhibit 5.1.

23.1              Consent of Deloitte & Touche LLP          Attached as Exhibit 23.1.

23.2              Consent of Graham & James LLP             Reference is made to Exhibit 5.1.

24.0              Power of Attorney                         Reference is made to p. 6.

</TABLE>

ITEM 9. UNDERTAKINGS.

    (a) The undersigned Registrant hereby undertakes:

        (1)  To file, during any period in which offers or sales are being made,
             a post-effective amendment to this Registration Statement:

             (i)   To include any prospectus required by Section 10 (a)(3) of
                   the Securities Act of 1933 (the "Securities Act");

             (ii)  To reflect in the prospectus any facts or events arising
                   after the effective date of the Registration Statement
                   (or the most recent post-effective amendment thereof) which,
                   individually or in the aggregate, represent a fundamental
                   change in the information set forth in the Registration
                   Statement.  Notwithstanding the

                                       3
<PAGE>


                   foregoing, any increase or decrease in volume of securities
                   offered (if the total dollar value of securities offered
                   would not exceed that which was registered) and any deviation
                   from the low or high end of the estimated maximum offering
                   range may be reflected in the form of prospectus filed with
                   the Securities and Exchange Commission pursuant to Rule
                   424(b) if, in the aggregate, the changes in volume and price
                   represent no more than a 20% change in the maximum aggregate
                   offering price set forth in the "Calculation of Registration
                   Fee" table in the effective Registration Statement;

             (iii) To include any material information with respect to the plan
                   of distribution not previously disclosed in the Registration
                   Statement or any material change to such information in the
                   Registration Statement.

                   Provided, however, that paragraphs (1)(i) and (1)(ii) do not
                   apply if the Registration Statement is on Form S-3, Form S-8
                   or Form F-3, and the information required to be included in a
                   post-effective amendment by those paragraphs is contained in
                   periodic reports filed with or furnished to the Securities
                   and Exchange Commission by the Registrant pursuant to
                   Section 13 or Section 15(d) of the Securities Exchange Act
                   of 1934 (the "Exchange Act") that are incorporated by
                   reference in this Registration Statement.

        (2)  That, for the purpose of determining any liability under the
             Securities Act, each such post-effective amendment shall be
             deemed to be a new registration statement relating to the
             securities offered therein, and the offering of such securities
             at that time shall be deemed to be the initial bona fide offering
             thereof.

        (3)  To remove from registration by means of a post-effective amendment
             any of the securities which remain unsold at the termination of the
             offering.

        (4)  That, for purposes of determining any liability under the
             Securities Act, each filing of the Registrant's annual report
             pursuant to Section 13(a) or Section 15(d) of the Exchange Act
             (and, where applicable, each filing of an employee benefit plan's
             annual report pursuant to Section 15(d) of the Exchange Act) that
             is incorporated by reference in the registration statement shall be
             deemed to be a new registration statement relating to the
             securities offered therein, and the offering of such securities at
             that time shall be deemed to be the initial bona fide offering
             thereof.

        (5)  Insofar as indemnification for liabilities arising under the
             Securities Act may be permitted to directors, officers and
             controlling persons of the Registrant pursuant to the foregoing
             provisions, or otherwise, the Registrant has been advised that
             in the opinion of the Securities and Exchange Commission such
             indemnification is against public policy as expressed in the
             Securities Act and is, therefore, unenforceable.  In the event
             that a claim for indemnification against such liabilities (other
             than the payment by the Registrant of expenses incurred or paid
             by a director, officer or controlling person of the Registrant in
             the successful defense of any action, suit or proceeding) is
             asserted by such director, officer or controlling person in
             connection with the securities being registered, the Registrant
             will, unless in the opinion of its counsel the matter has been
             settled by controlling precedent, submit to a court of appropriate
             jurisdiction the question whether such indemnification by it is
             against public policy as expressed in the Securities Act and will
             be governed by the final adjudication of such issue.

                                       4
<PAGE>



                                    SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the
registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of San Francisco, State of California,
on January 26, 2000.

                                     UNIONBANCAL CORPORATION


                                     By   /s/ Takahiro Moriguchi
                                          ------------------------
                                          Takahiro Moriguchi
                                          President and Chief Executive Officer


                                       5
<PAGE>


                                 POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears
below constitutes and appoints Takahiro Moriguchi, as his or her true and
lawful attorneys-in-fact and agents, with full power of substitution and
resubstitution, for him or her and in his or her name, place and stead, in
any and all capacities, to sign any and all amendments (including
post-effective amendments) to this Registration Statement, and to file the
same, with all exhibits thereto, and other documents in connection therewith,
with the Securities and Exchange Commission, granting unto said
attorneys-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite and necessary to be
done in connection therewith as fully to all intents and purposes as he or
she might or could do in person, hereby ratifying and confirming all that
said attorneys-in-fact and agents, or either of them, or their or his
substitute or substitutes, may lawfully do or cause to be done by virtue
thereof.

Pursuant to the requirements of the Securities Act of 1933, as amended,
this registration statement has been signed by the following persons
in the capacities and on the dates indicated.


<TABLE>
<CAPTION>

SIGNATURE                           TITLE                              DATE
---------                           -----                              ----
<S>                                 <C>                                <C>

/s/ Takahiro Moriguchi
----------------------              President and Chief Executive      January 26, 2000
Takahiro Moriguchi                  Officer and Director

/s/ David I. Matson
-------------------                 Chief Financial Officer            January 26, 2000
David I. Matson

/s/ David A. Anderson
---------------------               Controller                         January 26, 2000
David A. Anderson


------------------                  Director
Richard D. Farman

/s/ Stanley F. Farrar
---------------------               Director                           January 26, 2000
Stanley F. Farrar

/s/ Herman E. Gallegos
----------------------              Director                           January 26, 2000
Herman E. Gallegos


</TABLE>

                                       6
<PAGE>



<TABLE>
<CAPTION>

SIGNATURE                           TITLE                              DATE
---------                           -----                              ----
<S>                                 <C>                                <C>

/s/ Jack L. Hancock
-------------------                 Director                           January 26, 2000
Jack L. Hancock

/s/ Richard C. Hartnack
-----------------------             Director and Vice Chairman         January 26, 2000
Richard C. Hartnack

/s/ Kaoru Hayama
-------------------                 Director and Chairman              January 26, 2000
Kaoru Hayama


-------------------                 Director
Satoru Kishi

/s/ Harry W. Low
-------------------                 Director                           January 26, 2000
Harry W. Low

/s/ Mary S. Metz
-------------------                 Director                           January 26, 2000
Mary S. Metz

/s/ Raymond E. Miles
--------------------                Director                           January 26, 2000
Raymond E. Miles

/s/ J. Fernando Niebla
----------------------              Director                           January 26, 2000
J. Fernando Niebla

/s/ Sidney R. Petersen
----------------------              Director                           January 26, 2000
Sidney R. Petersen

/s/ Carl W. Robertson
---------------------               Director                           January 26, 2000
Carl W. Robertson

</TABLE>

                                       7
<PAGE>


<TABLE>
<CAPTION>

SIGNATURE                           TITLE                              DATE
---------                           -----                              ----
<S>                                 <C>                                <C>

/s/ Yoshihiko Someya
--------------------                Director and Deputy Chairman       January 26, 2000
Yoshihiko Someya


----------------                    Director
Henry T. Swigert

/s/ Robert M. Walker
--------------------                Director and Vice Chairman         January 26, 2000
Robert M. Walker

/s/ Hiroshi Watanabe
--------------------                Director                           January 26, 2000
Hiroshi Watanabe


----------------                    Director
Kenji Yoshizawa

</TABLE>


                                       8
<PAGE>


                                     EXHIBIT INDEX

<TABLE>
<CAPTION>

EXHIBIT                                                                      SEQUENTIAL
NUMBER                        EXHIBIT DESCRIPTION                               PAGE
---------                     -------------------                               ----
                                                                               NUMBER
                                                                               ------

<S>        <C>                                                                <C>

 4.1       Year 2000 UnionBanCal Corporation Management Stock Plan               N/A
 5.1       Opinion of Graham & James LLP                                       page 10
23.1       Consent of Deloitte & Touche LLP                                    page 12
23.2       Consent of Graham & James LLP  (Reference is made to Exhibit 5.1)     N/A
24.0       Power of Attorney (Reference is made to page 6)                       N/A



</TABLE>

                                       9
[{"type": "S-8", "sequence": "1", "description": "S-8", "secsgml_size_bytes": 20670}]
{"company-data": {"conformed-name": "UNIONBANCAL CORP", "cik": "0001011659", "assigned-sic": "6021", "irs-number": "941234979", "state-of-incorporation": "CA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-95497", "film-number": "514737"}, "business-address": {"street1": "350 CALIFORNIA ST", "city": "SAN FRANCISCO", "state": "CA", "zip": "94104-1476", "phone": "4157652575"}, "mail-address": {"street1": "350 CALIFORNIA ST", "city": "SAN FRANCISCO", "state": "CA", "zip": "94104-1476"}}
As filed with the Securities and Exchange Commission on January 27, 2000

                SECURITIES AND EXCHANGE COMMISSION
                       Washington, DC  20549

                       ---------------------

                             FORM S-8
                      REGISTRATION STATEMENT
                              UNDER
                    THE SECURITIES ACT OF 1933

                       ---------------------

                       UNIONBANCAL CORPORATION
        (Exact name of registrant as specified in its charter)

          California                               94-1234979
  (State or other jurisdiction                  (I.R.S. Employer
  of incorporation or organization)            Identification No.)

     400 California Street
       San Francisco, CA                             94104
(Address of principal executive offices)           (Zip Code)

    YEAR 2000 UNIONBANCAL CORPORATION MANAGEMENT STOCK PLAN
                     (Full title of the Plan)

                    JOHN H. MCGUCKIN, JR., ESQ.
           Executive Vice President and General Counsel

                        UNIONBANCAL CORPORATION
                         400 California Street
                        San Francisco, CA 94104
                            (415) 765-2969

       (name, address, including zip code and telephone number,
               including area code, of agent for service)

                    CALCULATION OF REGISTRATION FEE
PROPOSED MAXIMUM    PROPOSED MAXIMUM
TITLE OF SECURITIES     AMOUNT TO BE    OFFERING PRICE        AGGREGATE          AMOUNT OF
TO BE REGISTERED         REGISTERED       PER SHARE          OFFERING PRICE    REGISTRATION FEE
-------------------     ------------    -----------------   -----------------  -----------------
Common Stock,           10,000,000(1)   $32.3125(2)         $323,125,000(2)    $85,305
no par value
(1) Estimated maximum aggregate number of shares of UnionBanCal Corporation
    Common Stock that may be awarded and/or sold pursuant to the Plan.

(2) Estimated solely for the purpose of computing the registration fee pursuant
    to Rule 457(c) on the basis of the average high and low prices for the
    Common Stock on January 24, 2000 as reported on the New York Stock Exchange.
PART I

                  INFORMATION REQUIRED IN THE SECTION 10 (a) PROSPECTUS

ITEM 1. PLAN INFORMATION.

      The document(s) containing the information specified in Item 1 will be
sent or given to participants in the Year 2000 UnionBanCal Corporation
Management Stock Plan (the "Plan") as specified in Rule 428(b)(1) and is not
required to be filed as part of the registration statement.

ITEM 2. REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION.

      The document(s) containing the information specified in Item 2 will be
sent or given to participants in the Plan as specified in Rule 428(b)(1) and
is not required to be filed as part of this registration statement.

                                         PART II

                     INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

This Registration Statement covers shares of Common Stock of UnionBanCal
Corporation (the "Registrant") that have been authorized for issuance
pursuant to the Registrant's Plan.

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

      There are hereby incorporated by reference in this Registration
Statement the following documents and information heretofore filed with the
Commission.

    (a) The Registrant's Annual Report filed on Form 10-K
        for the fiscal year ended December 31, 1998.

    (b) The Registrant's proxy statement in connection with the Annual
        Meeting of Shareholders of Common Stock of the Registrant held
        on May 26, 1999.

    (c) All other reports filed pursuant to Section 13(a) or 15(d) of the
        Exchange Act since the end of the fiscal year covered by the
        Registrant's Annual Report on Form 10-K referred to in (a) above.

    (d) The description of the Registrant's Common Stock, no par value,
        contained in the Registrant's Registration Statement on Form 8-A,
        dated June 7, 1999, filed pursuant to Section 12(g) of the Securities
        Exchange Act of 1934, as amended (the "Exchange Act").

    All documents filed by the Registrant subsequently pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act before the filing of a
post-effective amendment which indicates that all securities offered hereby
have been sold or which deregisters all securities then remaining unsold,
shall be deemed to be incorporated by reference in this Registration
Statement and to be a part hereof from the date of filing of such documents.

ITEM 4. DESCRIPTION OF SECURITIES.

      Not applicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

      Not applicable.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

      Sections 204 (a) and 317 of the California General Corporation Law
("CCGL") authorize a corporation to indemnify its directors and officers
against certain liabilities and to eliminate their liability to the
corporation except in certain circumstances.  The Registrant's Amended and
Restated Articles of Incorporation contain a provision

                                       2
limiting the liability of the Registrant's directors for monetary damages to
the fullest extent permitted by California law. The Registrant's Amended and
Restated Articles of Incorporation contain a provision pursuant to which the
Registrant is authorized to indemnify its directors, officers, employees and
other agents through Bylaw provisions in excess to the indemnification
permitted by Section 317 of the CCGL subject only to the applicable limits as
set forth in Section 204 of the CCGL.

      In addition, the Registrant's Bylaws contain a provision limiting the
liability of the Registrant's directors for monetary damages to the fullest
extent permitted by California law and providing for indemnification to its
directors, officers, employees and other agents.  Moreover, under California
law each director is subject to liability for breach of the director's duty
of loyalty to the Company, for acts or omissions involving intentional
misconduct or knowing and culpable violations of law, for acts or omissions
that the director believes to be contrary to the best interest of the Company
or its shareholders or that involve the absence of good faith on the part of
the director, for any transaction from which the director derived an improper
personal benefit, for acts or omissions involving a reckless disregard for
the director's duty to the Registrant or its shareholders when the director
was aware or should have been aware of a risk of serious injury to the
Registrant or its shareholders, for acts or omissions that constitute an
unexcused pattern of inattention that amount to an abdication of the
director's duty to the Registrant or its shareholders, for improper
transactions between the director and the Registrant, for improper
distributions to shareholders, and for loans to officers and directors.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED.

      Not applicable.

ITEM 8. EXHIBITS.
REGULATION S-K                                              REFERENCE TO PRIOR FILING OR
EXHIBIT NO.       DESCRIPTION                               EXHIBIT NO. ATTACHED HERETO
--------------    -----------                               ----------------------------
4.1              Year 2000 UnionBanCal Corporation         Filed as Exhibit A to Registrant's proxy
                  Management Stock Plan                     statement in connection with the Annual
                                                            Meeting of Shareholders of Common
                                                            Stock of the Registrant held on May 26,
                                                            1999 and filed with the SEC on April 29,
                                                            1999 under file number 333-03040 and
                                                            incorporated by reference herein.

 5.1              Opinion of Graham & James LLP             Attached as Exhibit 5.1.

23.1              Consent of Deloitte & Touche LLP          Attached as Exhibit 23.1.

23.2              Consent of Graham & James LLP             Reference is made to Exhibit 5.1.

24.0              Power of Attorney                         Reference is made to p. 6.
ITEM 9. UNDERTAKINGS.

    (a) The undersigned Registrant hereby undertakes:

        (1)  To file, during any period in which offers or sales are being made,
             a post-effective amendment to this Registration Statement:

             (i)   To include any prospectus required by Section 10 (a)(3) of
                   the Securities Act of 1933 (the "Securities Act");

             (ii)  To reflect in the prospectus any facts or events arising
                   after the effective date of the Registration Statement
                   (or the most recent post-effective amendment thereof) which,
                   individually or in the aggregate, represent a fundamental
                   change in the information set forth in the Registration
                   Statement.  Notwithstanding the

                                       3
foregoing, any increase or decrease in volume of securities
                   offered (if the total dollar value of securities offered
                   would not exceed that which was registered) and any deviation
                   from the low or high end of the estimated maximum offering
                   range may be reflected in the form of prospectus filed with
                   the Securities and Exchange Commission pursuant to Rule
                   424(b) if, in the aggregate, the changes in volume and price
                   represent no more than a 20% change in the maximum aggregate
                   offering price set forth in the "Calculation of Registration
                   Fee" table in the effective Registration Statement;

             (iii) To include any material information with respect to the plan
                   of distribution not previously disclosed in the Registration
                   Statement or any material change to such information in the
                   Registration Statement.

                   Provided, however, that paragraphs (1)(i) and (1)(ii) do not
                   apply if the Registration Statement is on Form S-3, Form S-8
                   or Form F-3, and the information required to be included in a
                   post-effective amendment by those paragraphs is contained in
                   periodic reports filed with or furnished to the Securities
                   and Exchange Commission by the Registrant pursuant to
                   Section 13 or Section 15(d) of the Securities Exchange Act
                   of 1934 (the "Exchange Act") that are incorporated by
                   reference in this Registration Statement.

        (2)  That, for the purpose of determining any liability under the
             Securities Act, each such post-effective amendment shall be
             deemed to be a new registration statement relating to the
             securities offered therein, and the offering of such securities
             at that time shall be deemed to be the initial bona fide offering
             thereof.

        (3)  To remove from registration by means of a post-effective amendment
             any of the securities which remain unsold at the termination of the
             offering.

        (4)  That, for purposes of determining any liability under the
             Securities Act, each filing of the Registrant's annual report
             pursuant to Section 13(a) or Section 15(d) of the Exchange Act
             (and, where applicable, each filing of an employee benefit plan's
             annual report pursuant to Section 15(d) of the Exchange Act) that
             is incorporated by reference in the registration statement shall be
             deemed to be a new registration statement relating to the
             securities offered therein, and the offering of such securities at
             that time shall be deemed to be the initial bona fide offering
             thereof.

        (5)  Insofar as indemnification for liabilities arising under the
             Securities Act may be permitted to directors, officers and
             controlling persons of the Registrant pursuant to the foregoing
             provisions, or otherwise, the Registrant has been advised that
             in the opinion of the Securities and Exchange Commission such
             indemnification is against public policy as expressed in the
             Securities Act and is, therefore, unenforceable.  In the event
             that a claim for indemnification against such liabilities (other
             than the payment by the Registrant of expenses incurred or paid
             by a director, officer or controlling person of the Registrant in
             the successful defense of any action, suit or proceeding) is
             asserted by such director, officer or controlling person in
             connection with the securities being registered, the Registrant
             will, unless in the opinion of its counsel the matter has been
             settled by controlling precedent, submit to a court of appropriate
             jurisdiction the question whether such indemnification by it is
             against public policy as expressed in the Securities Act and will
             be governed by the final adjudication of such issue.

                                       4
SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the
registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of San Francisco, State of California,
on January 26, 2000.

                                     UNIONBANCAL CORPORATION

                                     By   /s/ Takahiro Moriguchi
                                          ------------------------
                                          Takahiro Moriguchi
                                          President and Chief Executive Officer

                                       5
POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears
below constitutes and appoints Takahiro Moriguchi, as his or her true and
lawful attorneys-in-fact and agents, with full power of substitution and
resubstitution, for him or her and in his or her name, place and stead, in
any and all capacities, to sign any and all amendments (including
post-effective amendments) to this Registration Statement, and to file the
same, with all exhibits thereto, and other documents in connection therewith,
with the Securities and Exchange Commission, granting unto said
attorneys-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite and necessary to be
done in connection therewith as fully to all intents and purposes as he or
she might or could do in person, hereby ratifying and confirming all that
said attorneys-in-fact and agents, or either of them, or their or his
substitute or substitutes, may lawfully do or cause to be done by virtue
thereof.

Pursuant to the requirements of the Securities Act of 1933, as amended,
this registration statement has been signed by the following persons
in the capacities and on the dates indicated.
SIGNATURE                           TITLE                              DATE
---------                           -----                              ----
/s/ Takahiro Moriguchi
----------------------              President and Chief Executive      January 26, 2000
Takahiro Moriguchi                  Officer and Director

/s/ David I. Matson
-------------------                 Chief Financial Officer            January 26, 2000
David I. Matson

/s/ David A. Anderson
---------------------               Controller                         January 26, 2000
David A. Anderson

------------------                  Director
Richard D. Farman

/s/ Stanley F. Farrar
---------------------               Director                           January 26, 2000
Stanley F. Farrar

/s/ Herman E. Gallegos
----------------------              Director                           January 26, 2000
Herman E. Gallegos
6
SIGNATURE                           TITLE                              DATE
---------                           -----                              ----
/s/ Jack L. Hancock
-------------------                 Director                           January 26, 2000
Jack L. Hancock

/s/ Richard C. Hartnack
-----------------------             Director and Vice Chairman         January 26, 2000
Richard C. Hartnack

/s/ Kaoru Hayama
-------------------                 Director and Chairman              January 26, 2000
Kaoru Hayama

-------------------                 Director
Satoru Kishi

/s/ Harry W. Low
-------------------                 Director                           January 26, 2000
Harry W. Low

/s/ Mary S. Metz
-------------------                 Director                           January 26, 2000
Mary S. Metz

/s/ Raymond E. Miles
--------------------                Director                           January 26, 2000
Raymond E. Miles

/s/ J. Fernando Niebla
----------------------              Director                           January 26, 2000
J. Fernando Niebla

/s/ Sidney R. Petersen
----------------------              Director                           January 26, 2000
Sidney R. Petersen

/s/ Carl W. Robertson
---------------------               Director                           January 26, 2000
Carl W. Robertson
7
SIGNATURE                           TITLE                              DATE
---------                           -----                              ----
/s/ Yoshihiko Someya
--------------------                Director and Deputy Chairman       January 26, 2000
Yoshihiko Someya

----------------                    Director
Henry T. Swigert

/s/ Robert M. Walker
--------------------                Director and Vice Chairman         January 26, 2000
Robert M. Walker

/s/ Hiroshi Watanabe
--------------------                Director                           January 26, 2000
Hiroshi Watanabe

----------------                    Director
Kenji Yoshizawa
8
EXHIBIT INDEX
EXHIBIT                                                                      SEQUENTIAL
NUMBER                        EXHIBIT DESCRIPTION                               PAGE
---------                     -------------------                               ----
                                                                               NUMBER
                                                                               ------
4.1       Year 2000 UnionBanCal Corporation Management Stock Plan               N/A
 5.1       Opinion of Graham & James LLP                                       page 10
23.1       Consent of Deloitte & Touche LLP                                    page 12
23.2       Consent of Graham & James LLP  (Reference is made to Exhibit 5.1)     N/A
24.0       Power of Attorney (Reference is made to page 6)                       N/A
9