As filed with the Securities and Exchange Commission on June 7, 2004
                                                 Registration No: 333-________

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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

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                                    FORM S-8

                             REGISTRATION STATEMENT
                                      Under
                           THE SECURITIES ACT OF 1933

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                               UNOCAL CORPORATION
               (Exact name of registrant specified in its charter)

            Delaware                               95-3825062
(State or other jurisdiction of           (I.R.S. Employer Identification No.)
 incorporation or organization)

         2141 Rosecrans Avenue, Suite 4000, El Segundo, California 90245
          (Address, including zip code, of Principal Executive Offices)

                      2004 DIRECTORS' DEFERRED COMPENSATION
                      AND RESTRICTED STOCK UNIT AWARD PLAN
                            (Full title of the plan)

                               SAMUEL H. GILLESPIE
         Senior Vice President, Chief Legal Officer and General Counsel
         2141 Rosecrans Avenue, Suite 4000, El Segundo, California 90245
                                 (310) 726-7600
            (Name, address, including zip code, and telephone number,
                   including area code, of agent for service)




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                         CALCULATION OF REGISTRATION FEE
                                                                                               

--------------------------------- --------------------- ------------------------- ------------------------ -----------------
      Title of each class                                   Proposed maximum         Proposed maximum
         of securities                Amount to be         offering price per       aggregate offering        Amount of
        to be registered               registered               unit(1)                  price(1)          registration fee
--------------------------------- --------------------- ------------------------- ------------------------ -----------------
--------------------------------- --------------------- ------------------------- ------------------------ -----------------
Common Stock, $1.00 par value        500,000 shares           $35.03                 $17,515,000             $2,219
per share (including Preferred
Stock Purchase Rights)
--------------------------------- --------------------- ------------------------- ------------------------ -----------------


(1) Solely for the purpose of calculating the registration fee in accordance
with Rule 457(c), based upon the average of the high and low prices reported in
the consolidated reporting system for June 4, 2004.









                PART II - INFORMATION NOT REQUIRED IN PROSPECTUS

Item 3.  Incorporation of Documents by Reference.

There are hereby incorporated by reference in this registration statement the
following documents heretofore filed with the Securities and Exchange Commission
(the "Commission"):

a.    Our Annual Report on Form 10-K, as amended on Form 10-K/A, for the fiscal
      year ended December 31, 2003;

b.    Our Quarterly Reports on Form 10-Q for the quarterly period ended March
      31, 2004;

c.   Our Current  Reports on Form 8-K dated (date of  earliest  event  reported)
     January 13 and 27, February 25, March 11, and May 25, 2004;

d.   All of our other  reports  filed  pursuant to Section 13(a) or 15(d) of the
     Securities  Exchange Act of 1934, as amended (the  "Exchange  Act"),  since
     December 31, 2003; and

e.   The description of our Common Stock,  $1.00 par value per share,  excluding
     that of the associated Preferred Stock Purchase Rights, set forth under the
     caption "Description of the Common Stock," included in the prospectus dated
     September 25, 1998,  of Union Oil Company of  California  and us (File Nos.
     333-58415  and  333-58415-01),  together  with the  description  of our now
     associated  Preferred  Share Purchase Rights included in our Current Report
     on Form 8-K dated  January 5, 2000,  as they have been amended as set forth
     in our Current  Reports on Form 8-K dated (date of earliest event reported)
     March  27  and  August  2,  2002.  The  descriptions  of  the  6.25%  Trust
     Convertible  Preferred  Securities  of Unocal  Capital  Trust,  (the "Trust
     Convertible  Preferred  Securities"),  the guarantee thereof by us, and our
     6.25% Convertible Junior  Subordinated  Debentures (as the rights and terms
     of which may  materially  limit or  qualify  the  rights  evidenced  by, or
     amounts  payable  with  respect  to, our common  stock) set forth under the
     captions  "Description  of the  Trust  Convertible  Preferred  Securities,"
     "Description   of  the   Guarantee,"   "Description   of  the   Convertible
     Debentures,"  and "Effect of Obligations  under the Convertible  Debentures
     and the Guarantee" in the prospectus dated August 7, 1996,  included in the
     Registration Statement on Form S-4 of Unocal and Unocal Capital Trust (File
     Nos. 333-09137 and 333-09137-01), as amended by Pre-Effective Amendment No.
     1.

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

Item 5.  Interests of Named Experts and Counsel.

Legal matters in connection with the issuance and sale of the securities offered
hereby will be passed upon by Samuel H. Gillespie, Senior Vice President,
Chief Legal Officer and General

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Counsel of the Company. As of June 1, 2004, Mr. Gillespie owned beneficially
14,821 shares of Common Stock. He also held an option to purchase 16,360 shares
of common stock at the price of $36.869 which expires on February 10, 2014. In
addition, Mr. Gillespie held 8,389 performance share units, which could be paid
out in up to 16,778 shares of common stock on December 31, 2006, based upon the
extent of the Company's achievement of performance goals determined within the
first 90 days of the award period that began January 1, 2004.

Item 6.  Indemnification of Directors and Officers.

Section 145 of the Delaware General Corporation Law authorizes Unocal to
indemnify directors and officers in certain circumstances against liabilities,
including expenses, incurred while acting in such capacities; provided,
generally, that any such indemnified director or officer acted in good faith and
in a manner he or she reasonably believed to be in the best interests of the
corporation and, in the case of a criminal proceeding, had no reasonable cause
to believe his or her conduct was unlawful. The Bylaws of Unocal provide for the
indemnification of directors and officers to the maximum extent permitted by the
Delaware General Corporation Law.

In addition, Unocal has provided in its Restated Certificate of Incorporation
that it shall eliminate the personal liability of its directors to the fullest
extent permitted by the Delaware General Corporation Law and Unocal has entered
into indemnification agreements with each of its directors and officers
providing for additional indemnification. Unocal has policies of directors' and
officers' liability insurance which insure directors and officers against the
costs of defense, settlement or payment of a judgment under certain
circumstances.

Item 8.  Exhibits.

The Exhibit Index lists the exhibits that are filed as part of this registration
statement.

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:

          a.   To include any  prospectus  required  by Section  10(a)(3) of the
               Securities Act of 1933, as amended (the "Securities Act");

          b.   To reflect in the  prospectus  any facts or events  arising after
               the effective  date of this  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   this   registration   statement.
               Notwithstanding the 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 Commission pursuant to

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               Rule 424(b) if, in the aggregate, the  changes  in  volume  and
               price  represent  no more than a 20 percent change in the
               maximum aggregate  offering price set forth in the  calculation
               of  Registration  Fee table in the effective registration
               statement;

          c.   To include  any  material  information  with  respect to the plan
               distribution  not  previously  disclosed in this statement or any
               material  change  to  such   information  in  this   registration
               statement;

     2.   Provided,  however,  that the undertakings set forth in paragraphs (a)
          and (b) above do not apply if the information  required to be included
          in a  post-effective  amendment  by those  paragraphs  is contained in
          periodic reports filed with the Commission by the Registrant  pursuant
          to  Section  13 or Section  15(d) of the  Securities  Act of 1934 (the
          "Exchange   Act")  that  are   incorporated   by   reference  in  this
          registration statement.

     3.   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.

     4.   To remove from  registration by means of a  post-effective  amendment,
          any of the  securities  being  registered  which remain  unsold at the
          termination of the offering.

b.   The  undersigned   Registrant  hereby  undertakes  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 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.

c.   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  Commission  such
     indemnification  is against  public  policy as expressed in the 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 Act and will be governed by the final adjudication of such issue.

                                   SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, 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

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duly caused this registration statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of El Segundo, State of
California, on June 7, 2004.

                            UNOCAL CORPORATION


                            By /S/ Joe D. Cecil
                              _______________________
                              Joe D. Cecil
                              Vice President and Comptroller


Pursuant to the requirements of the Securities Act of 1933, this registration
statement has been signed by the following persons in the capacities and on the
date indicated:




                SIGNATURE                                     TITLE                                 DATE
                ---------                                     -----                                 ----
                                                                                         

         /S/ Charles R. Williamson *          Chairman of the Board of Directors,              June 7, 2004
         _______________________             Chief Executive Officer and President
          Charles R. Williamson                   (Principal Executive Officer)

         /S/ Terry G. Dallas *                       Executive Vice President                   June 7, 2004
         _______________________                   and Chief Financial Officer
             Terry G. Dallas

         /S/ Joe D. Cecil                         Vice President and Comptroller                June 7, 2004
         _______________________                  (Principal Accounting Officer)
               Joe D. Cecil

         /S/ John W. Creighton, Jr. *                  Vice Chairman of the                     June 7, 2004
         _______________________                        Board of Directors
          John W. Creighton, Jr.

         /S/ Craig Arnold *                                  Director                           June 7, 2004
         _______________________
               Craig Arnold

         /S/ James W. Crownover *                            Director                           June 7, 2004
         _______________________
            James W. Crownover

         /S/ Ferrell P. McClean *                            Director                           June 7, 2004
         _______________________
            Ferrell P. McClean

         /S/ Richard D. McCormick *                          Director                           June 7, 2004
         _______________________
           Richard D. McCormick

         /S/ Donald B. Rice *                                Director                           June 7, 2004
         _______________________
              Donald B. Rice

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                SIGNATURE                                     TITLE                                 DATE
                ---------                                     -----                                 ----


         -----------------------                             Director
             Kevin W. Sharer

         /S/ Mark A. Suwyn *                                 Director                           June 7, 2004
         _______________________
              Mark A. Suwyn

        /S/ Marina v.N. Whitman *
        _______________________                              Director                           June 7, 2004
           Marina v.N. Whitman




* By /S/ Joe D. Cecil
     _____________________
      Joe D. Cecil
      Attorney-in-Fact



Pursuant to the requirements of the Securities Act of 1933, the members of the
Board Governance Committee who administer the 2004 Directors' Deferred
Compensation and Restricted Stock Unit Award Plan, have duly caused this
registration statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of El Segundo, State of California, June 7, 2004.

                          2004 DIRECTORS' DEFERRED
                          COMPENSATION AND RESTRICTED STOCK
                          UNIT AWARD PLAN


                          By /S/ Donald B. Rice *
                             ________________________
                             Donald B. Rice
                             Chair, Board Governance Committee


                            * By /S/ Joe D. Cecil
                                 ____________________
                                  Joe D. Cecil
                                  Attorney-in-Fact

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                                  EXHIBIT INDEX
EXHIBIT
NUMBER                               EXHIBIT

4.1      Restated Certificate of Incorporation of Unocal, dated as of January
         31, 2000, and currently in effect (incorporated by reference to Exhibit
         3.1 to Unocal's Annual Report on Form 10-K for the year ended December
         31, 1999, File No. 1-8483). *

4.2      Bylaws of Unocal, as amended through May 24, 2004, and currently in
         effect (incorporated by reference to Exhibit 4.2 to Unocal's
         Registration Statement on Form S-8 filed June 7, 2004,
         File No. 333-116238). *

4.3      Rights Agreement, dated as of January 5, 2000, between Unocal and
         Mellon Investor Services, L.L.C., as Rights Agent (incorporated by
         reference to Exhibit 4 to Unocal's Current Report on Form 8-K dated
         January 5, 2000, File No. 1-8483), as amended by Amendment to Rights
         Agreement, dated as of March 27, 2002 (incorporated by reference to
         Exhibit 10 to Unocal's Current Report on Form 8-K dated March 27, 2002,
         File No. 1-8483), and as further amended by Amendment No. 2 to Rights
         Agreement, dated as of August 2, 2002 (incorporated by reference to
         Exhibit 10 to Unocal's Current Report on Form 8- K dated August 2,
         2002, File No. 1-8483). *

5        Opinion of Samuel H. Gillespie, Senior Vice President, Chief Legal
         Officer and General Counsel of Unocal.

23.1     Consent of Independent Registered Public Accounting Firm.

23.2     Opinion of Samuel H. Gillespie, Senior Vice President, Chief Legal
         Officer and General Counsel of Unocal (included in Exhibit 5).

24       Power of Attorney.

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* Previously filed


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