POWER OF ATTORNEY


         By signing below, each of the undersigned officers and/or directors of
Unocal Corporation, a Delaware corporation, hereby constitutes and appoints
Timothy H. Ling, Joe D. Cecil and Darrell D. Chessum, and each of them
severally, with full power of substitution and resubstitution, as his or her
true and lawful attorneys-in-fact and agents to sign for the undersigned and in
the name of the undersigned, in any and all capacities, the Registration
Statement(s) on Form S-8 and/or S-3 to which this Power of Attorney shall be
filed as an exhibit and any or all amendments (including any post-effective
amendments) to such Registration Statement and to file the same with all
exhibits thereto, including this Power of Attorney, and any and all applications
and other documents in connection therewith, with the Securities and Exchange
Commission, granting unto said attorneys-in-fact and agents full power and
authority to do and perform any and all acts and things whatsoever required and
necessary to be done in and about the premises, as fully to all intents and
purposes as the undersigned could do if personally present. Each of the
undersigned hereby ratifies and confirms all that said attorneys-in-fact and
agents or their substitute or substitutes may lawfully do or cause to be done by
virtue hereof. This Power of Attorney may be signed in several counterparts.

         IN WITNESS WHEREOF, each of the undersigned has executed this Power of
Attorney as of March 27, 2001.

       SIGNATURE                                     TITLE
       ---------                                     -----

/S/ Charles R. Williamson
_________________________               Chief Executive Officer and Director
Charles R. Williamson

/S/ Timothy H. Ling
_________________________               Chief Operating Officer and Director
Timothy H. Ling

/S/ Terry G. Dallas
________________________                Chief Financial Officer
Terry G. Dallas

_________________________               Vice President and Comptroller
Joe D. Cecil                            (Principal Accounting Officer)

_________________________               Director
John W. Amerman

/S/ John W. Creighton, Jr.
_________________________               Director
John W. Creighton, Jr.



      SIGNATURE                         TITLE
      ---------                         -----

/S/ James W. Crownover
_________________________               Director
James W. Crownover

/S/ Frank C. Herringer
_________________________               Director
Frank C. Herringer

/S/ Donald B. Rice
_________________________               Director
Donald B. Rice

/S/ Kevin W. Sharer
_________________________               Director
Kevin W. Sharer

/S/ Marina v.N. Whitman
_________________________               Director
Marina v.N. Whitman


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