FORM 10-K/A                           2000

                                 UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549
(Mark One)
   [X]        ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                        SECURITIES EXCHANGE ACT OF 1934
                  For the Fiscal Year Ended December 31, 2000
                                      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 1-5153

                                USX CORPORATION
            (Exact name of registrant as specified in its charter)
              Delaware                                          25-0996816
      (State of Incorporation)              (I.R.S. Employer Identification No.)
                 600 Grant Street, Pittsburgh, PA  15219-4776
                   (Address of principal executive offices)
                            Tel. No. (412) 433-1121

         Securities registered pursuant to Section 12 (b) of the Act:*



=================================================================================================================================
                                                        Title of Each Class
---------------------------------------------------------------------------------------------------------------------------------
                                                                 
   USX-Marathon Group                                               8-3/4% Cumulative Monthly Income Preferred Shares,
        Common Stock, par value $1.00                                   Series A (Liquidation Preference $25 per share)**/(a)/
   USX-U. S. Steel Group                                            6.75% Convertible Quarterly Income Preferred
        Common Stock, par value $1.00                                   Securities (Initial Liquidation Amount $50 per
   6.50% Cumulative Convertible Preferred                               Security)***/(a)/
        (Liquidation Preference $50.00 per share)                   7%  Guaranteed Notes Due 2002 of Marathon Oil
                                                                        Company/(a)/
=================================================================================================================================


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 and (2) has been subject to such filing
requirements for at least the past 90 days.  Yes  X  No____
                                                 ---

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K (ss.229.405 of this chapter) 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. [_]

Aggregate market value of Common Stock held by non-affiliates as of January 31,
2001: $10 billion. The amount shown is based on the closing prices of the
registrant's Common Stocks on the New York Stock Exchange composite tape on that
date. Shares of Common Stock held by executive officers and directors of the
registrant are not included in the computation. However, the registrant has made
no determination that such individuals are "affiliates" within the meaning of
Rule 405 under the Securities Act of 1933.

There were 308,269,864 shares of USX-Marathon Group Common Stock and 88,767,023
shares of USX-U. S. Steel Group Common Stock outstanding as of January 31, 2001.

Documents Incorporated By Reference:
     Proxy Statement dated March 12, 2001 is incorporated in Part III. Proxy
     Statement dated March 9, 1998 is incorporated in Part IV.

__________
     *   These securities are listed on the New York Stock Exchange. In
         addition, the Common Stocks are listed on The Chicago Stock Exchange
         and the Pacific Exchange.
    **   Issued by USX Capital LLC.
   ***   Issued by USX Capital Trust I.
   /(a)/ Obligations of Marathon Oil Company, USX Capital LLC and USX Capital
         Trust I, all wholly owned subsidiaries of the registrant, have been
         guaranteed by the registrant.


                                    PART IV

Item 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

     A. Documents Filed as Part of the Report
     1. Financial Statements
        Financial Statements filed as part of this report are listed on
        the Index to Financial Statements, Supplementary Data,
        Management's Discussion and Analysis, and Quantitative and
        Qualitative Disclosures About Market Risk of USX Consolidated,
        the Marathon Group and the U. S. Steel Group, immediately
        preceding pages U-1, M-1 and S-1, respectively.

     2. Financial Statement Schedules and Supplementary Data
           The financial statement Schedule II - Valuation and
           Qualifying Accounts is included on page 60. All other
           schedules are omitted because they are not applicable or the
           required information is contained in the applicable
           financial statements or notes thereto.

           Report of Independent Accountants on Financial Statement Schedule is
           included on page 61.

           Supplementary Data -
           Summarized Financial Information of Marathon Oil Company is
           provided on page 63. Disclosures About Forward-Looking
           Statements are provided beginning on page 64.

     B. Reports on Form 8-K

        Form 8-K dated October 19, 2000, reporting under Item 5. Other
        Events and Regulation FD Disclosure, that the Marathon Group
        Earnings Release reported that Marathon has signed a definitive
        agreement with Shell to transfer its 37.5 percent interest in
        Sakhalin Energy Investment Company Ltd. The increased
        likelihood of closing this transaction triggered a one-time,
        noncash deferred tax charge of $235 million in the third
        quarter.

        Form 8-K dated November 22, 2000, reporting under Item 9.
        Regulation FD Disclosure, the press release titled "U. S. Steel
        Group Experiencing Coal Production Problems at Two Mines".

        Form 8-K dated November 29, 2000, reporting under Item 9.
        Regulation FD Disclosure, the press releases titled "Surma
        Named President of Marathon Ashland Petroleum LLC" and
        "Marathon Announces new Executive Vice President".

        Form 8-K dated November 30, 2000, reporting under Item 9.
        Regulation FD Disclosure, the press release titled "USX to
        Retain Advisors to Study its Capital Structure".

        Form 8-K dated November 30, 2000, reporting under Item 9.
        Regulation FD Disclosure, the press release titled "Marathon
        Reviews Progress of Upstream and Downstream Businesses".

        Form 8-K dated December 6, 2000, reporting under Item 9.
        Regulation FD Disclosure, the press release titled "Marathon
        Sakhalin Limited and Shell Sakhalin Holdings B.V. complete
        exchange agreement".

        Form 8-K dated December 28, 2000, reporting under Item 9.
        Regulation FD Disclosure, that in December 2000, USX-U. S.
        Steel Group made a voluntary $500 million contribution to the
        Voluntary Employee Benefit Association (VEBA), which was
        established as part of the 1994 agreement with the United
        Steelworkers of America to pay retiree health care and life
        insurance benefits for steelworker retirees.

        Form 8-K dated December 28, 2000, reporting under Item 9.
        Regulation FD Disclosure, the press release titled "Marathon
        and Kinder Morgan agree to form Permian Basin joint venture".

        Form 8-K dated January 24, 2001, reporting under Item 9.
        Regulation FD Disclosure, the USX-Marathon Group and USX-U. S.
        Steel Group Earnings Releases".

                                       56


        Form 8-K dated February 27, 2001, reporting under Item 5. Other
        Events, the filing of the audited Financial Statements and
        Supplementary Data for the fiscal year ended December 31, 2000,
        reports of independent accountants.

     C. Exhibits

Exhibit No.

     2. Plan of Acquisition, Reorganization, Arrangement
        Liquidation or Succession
          None

     3. Articles of Incorporation and By-Laws
        (a)  USX Restated Certificate of
          Incorporation dated May 1, 1999.......   Incorporated by reference to
                                                   Exhibit 3.1 to the USX Report
                                                   on Form 10-Q for the quarter
                                                   ended June 30, 1999.

        (b)  USX By-Laws, effective
             as of May 1, 1999..................   Incorporated by reference to
                                                   Exhibit 3.2 to the USX Report
                                                   on Form 10-Q for the quarter
                                                   ended June 30, 1999.

     4. Instruments Defining the Rights of Security Holders,
        Including Indentures
        (a)  Five-Year Credit Agreement dated
             as of November 30, 2000............

        (b)  Rights Agreement, dated as of
             September 28, 1999, between
             USX Corporation and ChaseMellon
             Shareholder Services, L.L.C.,
             as Rights Agent...................    Incorporated by reference to
                                                   Exhibit 4 to USX's Form 8-K
                                                   filed on September 28, 1999.

        (c)  Pursuant to 17 CFR 229.601(b)(4)(iii),
             instruments with respect to long-term debt
             issues have been omitted where the amount
             of securities authorized under such
             instruments does not exceed 10% of the total
             consolidated assets of USX. USX hereby agrees
             to furnish a copy of any such instrument to the
             Commission upon its request.

                                       57


     10. Material Contracts

         (a)  USX 1990 Stock Plan,
              As Amended April 28, 1998..........   Incorporated by reference to
                                                    Annex II to the USX Proxy
                                                    Statement dated March 9,
                                                    1998.

         (b)  USX Annual Incentive Compensation
              Plan, As Amended July 25, 2000.....

         (c)  USX Senior Executive Officer Annual
              Incentive Compensation Plan,
              As Amended April 28, 1998..........   Incorporated by reference to
                                                    Annex I to the USX Proxy
                                                    Statement dated March 9,
                                                    1998.

         (d)  Marathon Oil Company Annual
              Incentive Compensation Plan, As
              Amended November 23, 1999..........   Incorporated by reference to
                                                    Exhibit 10(d) of USX Form
                                                    10-K for the year ended
                                                    December 31, 1999.

         (e)  USX Executive Management
              Supplemental Pension Program,
              As Amended January 1, 1999.........   Incorporated by reference to
                                                    Exhibit 10(e) of USX Form
                                                    10-K for the year ended
                                                    December 31, 1999.

         (f)  USX Supplemental Thrift Program,
              As Amended January 1, 1999.........   Incorporated by reference to
                                                    Exhibit 10(f) of USX Form
                                                    10-K for the year ended
                                                    December 31, 1999.

         (g)  Amended and Restated Limited
              Liability Company Agreement of
              Marathon Ashland Petroleum LLC,
              dated as of December 31, 1998......   Incorporated by reference to
                                                    Exhibit 10(h) of USX Form
                                                    10-Q for the quarter ended
                                                    June 30, 1999.

         (h)  Amendment No. 1 dated as of
              December 31, 1998 to the Put/Call,
              Registration Rights and Standstill
              Agreement of Marathon Ashland
              Petroleum LLC dated as of
              January 1, 1998....................   Incorporated by reference to
                                                    Exhibit 10.2 of USX Form 8-K
                                                    dated January 1, 1998, and
                                                    Exhibit 10(i) of USX Form
                                                    10-Q for the quarter ended
                                                    June 30, 1999.

         (i)  Form of Severance Agreements
              between the Corporation and
              Various Officers...................   Incorporated by reference to
                                                    Exhibit 10 of USX Form 10-Q
                                                    for the quarter ended
                                                    September 30, 1999.

         (j)  USX Deferred Compensation Plan
              For Non-Employee Directors
              Amended as of January 1, 1998......

                                       58


         (k)  Agreement between Marathon
              Oil Company and Clarence P.
              Cazalot, Jr., executed
              February 28, 2000.................  Incorporated by reference to
                                                  Exhibit 10(k) of USX Form 10-K
                                                  for the year ended December
                                                  31, 1999.

         (l)  USX Non-Officer Restricted Stock
              Plan, effective January 30, 2001..

     12.1   Computation of Ratio of Earnings to Combined Fixed Charges and
            Preferred Stock Dividends

     12.2   Computation of Ratio of Earnings to Fixed Charges

     21.    List of Significant Subsidiaries

     23.    Consent of Independent Accountants

                                       59


          SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS AND RESERVES
              YEARS ENDED DECEMBER 31, 2000 AND DECEMBER 31, 1999
                             (Millions of Dollars)


                                                                   Additions
                                                     -------------------------------------
                                        Balance at    Charges to   Charges                                    Balance at
                                        Beginning     Costs and    to Other        Other                        End of
          Description                   of Period     Expenses     Accounts      Additions     Deductions/(a)/  Period
------------------------------------------------------------------------------------------------------------------------
                                                                                          
Year ended December 31, 2000:
 Reserves deducted in the
 balance sheet from the assets
 to which they apply:
  Allowance for doubtful accounts         $   12      $   19       $      -      $   37/(b)/   $     8        $   60
  Inventory market valuation reserve           -           -              -           -              -             -
  Investments and long-term
   receivables reserve                         3           -             36/(c)/      -              1            38
  Tax valuation allowances:
   Federal                                    30           -              -           -             30             -
   State                                      52           -              -           -              2            50
   Foreign                                   282           -              -           -             30           252

Year ended December 31, 1999:
 Reserves deducted in the
 balance sheet from the assets
 to which they apply:
  Allowance for doubtful accounts         $   12      $    5       $      -      $    4/(d)/   $     9        $   12
  Inventory market valuation reserve         551           -              -           -            551             -
  Investments and long-term
    receivabless reserve                      10           -              -           -              7             3
  Tax valuation allowances:
    Federal                                   30           -              -           -              -            30
    State                                     52           -              -           -              -            52
    Foreign                                  260           -             22/(e)/      -              -           282
------------------------------------------------------------------------------------------------------------------------


/(a)/ Deductions for the allowance for doubtful accounts and long-term
      receivables include amounts written off as uncollectible, net of
      recoveries. Deductions for the inventory market valuation reserve reflect
      increases in market prices and inventory turnover, resulting in noncash
      credits to costs and expenses. Reductions in the tax valuation allowances
      reflect changes in the amount of deferred taxes expected to be realized,
      resulting in credits to the provision for income taxes.
/(b)/ Includes $36 million relating to the acquisition of U. S. Steel Kosice
      s.r.o. and $1 million reclassification from long-term reserves.
/(c)/ Includes $36 million classified to dividend and investee income relating
      to a notes receivable from an equity investee.
/(d)/ Includes $2 million relating to the acquisition of Lorain Tubular LLC, and
      $2 million reclassification from long-term reserves.
/(e)/ Additions to the tax valuation allowances are included in the provision
      for income taxes.

                                      60


                     Report of Independent Accountants on
                         Financial Statement Schedule

To the Board of Directors
of USX Corporation:


Our audits of the consolidated financial statements referred to in our report
dated February 7, 2001 appearing in the Annual Report on Form 10-K/A of USX
Corporation dated September 14, 2001 also included an audit of the financial
statement schedule listed in Item 14(a)(2) of this Annual Report on Form 10-K/A.
In our opinion, this financial statement schedule presents fairly, in all
material respects, the information set forth therein when read in conjunction
with the related consolidated financial statements.

/s/ PricewaterhouseCoopers LLP
Pittsburgh, PA 15219-2974
February 7, 2001


                                      61


                                  SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, this report
has been signed below by the following persons on behalf of the registrant and
in the capacity indicated on October 11, 2001.

                                USX CORPORATION

                            By /s/ Larry G. Schultz
                               ----------------------------------
                                   Larry G. Schultz
                               Vice President - Accounting


               Signature                                 Title
               ---------                                 -----

                                                  Chairman of the Board &
                  *                         Chief Executive Officer and Director
----------------------------------------
           Thomas J. Usher
                                         Vice Chairman & Chief Financial Officer
                  *                                      and Director
----------------------------------------
         Robert M. Hernandez

/s/       Larry G. Schultz                      Vice President - Accounting
----------------------------------------
          Larry G. Schultz

                  *                                       Director
----------------------------------------
          Neil A. Armstrong

                  *                             Vice Chairman and Director
----------------------------------------
      Clarence P. Cazalot, Jr.

                  *                                       Director
----------------------------------------
           J. Gary Cooper

                  *                                       Director
----------------------------------------
          Charles A. Corry

                  *                                       Director
----------------------------------------
         Shirley Ann Jackson

                  *                                       Director
----------------------------------------
           Charles R. Lee

                  *                                       Director
----------------------------------------
            Paul E. Lego

                  *                                       Director
----------------------------------------
        John F. McGillicuddy

                  *                                       Director
----------------------------------------
          Seth E. Schofield

                  *                                       Director
----------------------------------------
            John W. Snow

                  *                                       Director
----------------------------------------
          Douglas C. Yearley

*By /s/   Larry G. Schultz
----------------------------------------
      Larry G. Schultz, Attorney-in-Fact

                                      62