1993
                                     ----
                      SECURITIES AND EXCHANGE COMMISSION
                           WASHINGTON, D. C.  20549
                                     
                                 FORM 10-K/A     
                                  
                               (AMENDMENT NO. 1)     

         X    ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
       -----  SECURITIES EXCHANGE ACT OF 1934 
              For the fiscal year ended December 31, 1993
                                        -----------------

                                       or
    
              TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
       -----  SECURITIES EXCHANGE ACT OF 1934 
              For the transition period from _____________ to ____________.

                         Commission file number 1-8483

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

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

 1201 WEST 5TH STREET, LOS ANGELES, CALIFORNIA                  90017
   (Address of Principal Executive Offices)                  (Zip Code)

      Registrant's Telephone Number, Including Area Code:  (213) 977-7600

          Securities Registered Pursuant to Section 12(b) of the Act:

      Title of each class            Name of each exchange on which registered
      -------------------            -----------------------------------------
    Common Stock, par value                 New York Stock Exchange
     $1.00 per share                        Chicago Stock Exchange
                                            Pacific Stock Exchange
    
    Stock Purchase Rights                   New York Stock Exchange
                                            Chicago Stock Exchange
                                            Pacific Stock Exchange      
 
       SECURITIES REGISTERED PURSUANT TO SECTION 12(G) OF THE ACT:  NONE

   Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.   Yes  X      No
                                               -----      -----     

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [X]

   The aggregate market value of Common Stock held by non-affiliates of the
registrant as of March 15, 1994 (based upon the average of the high and low
prices of these shares on the New York Stock Exchange Composite Transactions
listing) was $6,576 million.

   Shares of Common Stock outstanding as of March 15, 1994: 241,841,427

                      DOCUMENTS INCORPORATED BY REFERENCE

   Portions of 1994 Proxy Statement                   Part III



                                    PART III

   The information required by Items 10 through 12 (except for information
regarding the company's executive officers) is incorporated by reference from
Unocal's Proxy Statement for its 1994 Annual Meeting of Stockholders, 
File No. 1-8483, as indicated below.
 
. . . 

ITEM 11 - EXECUTIVE COMPENSATION
    
   See pages 6 and 12 through 15 of the 1994 Proxy Statement.     
 
. . . 

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                                   SIGNATURE
 
Pursuant to the requirements of the Securities Exchange Act of 1934, the 
registrant has duly caused this amendment to report to be signed on its behalf 
by the undersigned, thereunto duly authorized.
 
                                        UNOCAL CORPORATION
                                        ------------------
                                           (Registrant)
 
Dated: April 8, 1994                    By: CHARLES S. MCDOWELL
                                            -------------------
                                            (Charles S. McDowell,
                                            Vice President and Comptroller)

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                               UNOCAL CORPORATION

                                 EXHIBIT INDEX
    
Exhibit  3.1*                   Certificate of Incorporation of Unocal
                                (incorporated by reference to Exhibit 3 to
                                Unocal's Annual Report on Form 10-K for the year
                                ended December 31, 1990, File No. 1-8483).     
    
Exhibit  3.2*                   Bylaws of Unocal (incorporated by reference to
                                Exhibit 3 to Unocal's Quarterly Report on Form
                                10-Q for the quarter ended March 31, 1992, File
                                No. 1-8483. Amendments to bylaws to be effective
                                on and after April 25, 1994 are incorporated by
                                reference to Unocal's Current Report on Form 
                                8-K, dated March 2, 1994, File No. 1-8483).     
                                     
Exhibit  4*                     Instruments Defining the Rights of Security
                                Holders, Including Indentures - see pages 65 and
                                66.     
     
Exhibit 10.1*                   Rights Agreement, dated as of January 29, 1990,
                                between the registrant and Chemical Trust
                                Company of California, as successor Rights Agent
                                (incorporated by reference to Exhibit 1 to 
                                Unocal's Current Report on Form 8-K dated 
                                January 29, 1990, File No. 1-8483).     

The following Exhibits 10.2 through 10.8 are compensatory plans or agreements
required to be filed by Item 601(b)(10)(iii)(A) of Regulation S-K.
    
Exhibit 10.2*                   The Management Incentive Program (incorporated
                                by reference to Unocal Registration Statement 
                                on Form S-8, File No. 33-43231, filed October 
                                8, 1991).     
     
Exhibit 10.3*                   The Long-Term Incentive Plan of 1985
                                (incorporated by reference to Unocal
                                Registration Statement on Form S-8, File No. 
                                2-93452, filed September 28, 1984).     
                                    
Exhibit 10.4*                   Supplemental Retirement Plan for Key Management
                                Personnel, as amended and effective January 1,
                                1989 (incorporated by reference to Exhibit 10.3
                                to the Unocal's Report on Form 10-K for the year
                                ended December 31, 1990, File No. 1-8483).     
     
Exhibit 10.5*                   Other Compensatory Arrangements (incorporated by
                                reference to Exhibit 10.4 to Unocal's Annual
                                Report on Form 10-K for the year ended December
                                31, 1990, File No. 1-8483).     
     
Exhibit 10.6*                   Directors' Restricted Stock Plan of 1991
                                (incorporated by reference to Exhibit B to 
                                Unocal's Proxy Statement for its 1991 Annual 
                                Meeting of Stockholders, File No. 1-8483).     
    
Exhibit 10.7*                   Form of Indemnity Agreement between Unocal and
                                each of its directors (incorporated by reference
                                to Exhibit A to Unocal's Proxy Statement for its
                                1987 Annual Meeting of Stockholders, File No. 
                                1-8483).     
    
Exhibit 10.8**                  Consulting Agreement, dated April 26, 1993,
                                between Union Oil Company of California, dba
                                Unocal, and Claude S. Brinegar.     
    
Exhibit 11*                     Computation of Earnings Per Common Share     
     
Exhibit 12*                     Computation of Ratio of Earnings to Fixed 
                                Charges     
     
Exhibit 21*                     Subsidiaries of Unocal Corporation     
     
Exhibit 23*                     Consent of Coopers & Lybrand     
    
- ----------     
    
 * Previously filed.     
    
** Filed with this amendment.     

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