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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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

                                   FORM 10-Q/A

     [X]    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                       FOR THE PERIOD ENDED JUNE 30, 1999

                                       OR

     [ ]    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                        COMMISSION FILE NUMBER: 0-23653

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

                             HORIZON OFFSHORE, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

              DELAWARE                            76-0487309
   (STATE OR OTHER JURISDICTION OF             (I.R.S. EMPLOYER
   INCORPORATION OR ORGANIZATION)             IDENTIFICATION NO.)

                      2500 CITYWEST BOULEVARD, SUITE 2200
                              HOUSTON, TEXAS 77042
                    (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)
                                   (ZIP CODE)

                                 (713) 361-2600
              (REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE)

     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 [ ]

     The number of shares of the registrant's Common Stock outstanding as of
August 12, 1999 was 18,800,980.

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<PAGE>
                        PART I -- FINANCIAL INFORMATION

ITEM 1.  FINANCIAL STATEMENTS

                    HORIZON OFFSHORE, INC. AND SUBSIDIARIES
                          CONSOLIDATED BALANCE SHEETS
                (IN THOUSANDS, EXCEPT SHARE AND PER SHARE DATA)


                                            JUNE 30,        DECEMBER 31,
                                              1999              1998
                                           -----------      ------------
                                           (UNAUDITED)

                 ASSETS
CURRENT ASSETS:
     Cash and cash equivalents..........    $   7,641         $  9,649
     Accounts receivable --
          Contract receivables..........       16,651           25,549
          Costs in excess of billings...       14,183            9,546
          Related parties...............          136               82
     Income taxes receivable............          481              481
     Other current assets...............          618              642
                                           -----------      ------------
          Total current assets..........       39,710           45,949
PROPERTY AND EQUIPMENT, net.............      158,822          145,680
OTHER ASSETS............................        6,085            2,040
                                           -----------      ------------
                                            $ 204,617         $193,669
                                           ===========      ============
  LIABILITIES AND STOCKHOLDERS' EQUITY
CURRENT LIABILITIES:
     Accounts payable...................    $   3,206         $  7,654
     Accrued liabilities................        3,582            5,086
     Accrued job costs..................       10,162           10,334
     Billings in excess of costs........        1,578            2,608
     Current maturities of long-term
      debt..............................        9,694            7,606
                                           -----------      ------------
          Total current liabilities.....       28,222           33,288
LONG-TERM DEBT, net of current
  maturities............................       74,722           62,268
DUE TO RELATED PARTIES..................           32               20
DEFERRED INCOME TAXES...................        4,500            3,633
                                           -----------      ------------
          Total liabilities.............      107,476           99,209
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY:
     Preferred stock, $1 par value,
      5,000,000 shares authorized,
       none issued and outstanding......           --               --
     Common stock, $1 par value,
      35,000,000 shares authorized,
       19,826,480 shares issued at June
       30, 1999 and December 31, 1998...        9,119            9,119
     Additional paid-in capital.........       87,891           87,767
     Retained earnings..................        6,857            5,156
     Treasury stock, 1,025,500 shares at
      June 30, 1999 and 1,155,000 shares
      at December 31, 1998..............       (6,726)          (7,582)
                                           -----------      ------------
          Total stockholders' equity....       97,141           94,460
                                           -----------      ------------
                                            $ 204,617         $193,669
                                           ===========      ============

  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       2
<PAGE>
                    HORIZON OFFSHORE, INC. AND SUBSIDIARIES
                     CONSOLIDATED STATEMENTS OF OPERATIONS
                                  (UNAUDITED)
                (IN THOUSANDS, EXCEPT SHARE AND PER SHARE DATA)

<TABLE>
<CAPTION>
                                             THREE MONTHS ENDED               SIX MONTHS ENDED
                                                  JUNE 30,                        JUNE 30,
                                       ------------------------------  ------------------------------
                                            1999            1998            1999            1998
                                       --------------  --------------  --------------  --------------
<S>                                    <C>             <C>             <C>             <C>
CONTRACT REVENUES....................  $       23,437  $       34,311  $       35,793  $       52,922
COST OF CONTRACT REVENUES............          16,603          25,520          26,693          38,747
                                       --------------  --------------  --------------  --------------
     Gross profit....................           6,834           8,791           9,100          14,175
SELLING, GENERAL AND ADMINISTRATIVE
  EXPENSES...........................           2,129           1,803           4,470           3,742
                                       --------------  --------------  --------------  --------------
     Operating income................           4,705           6,988           4,630          10,433
OTHER INCOME (EXPENSE):
     Interest expense................          (1,508)           (380)         (2,467)         (1,214)
     Interest income and other.......             302              70             405             103
                                       --------------  --------------  --------------  --------------
NET INCOME BEFORE INCOME TAXES.......           3,499           6,678           2,568           9,322
PROVISION FOR INCOME TAX.............           1,194           1,879             867           1,879
                                       --------------  --------------  --------------  --------------
NET INCOME...........................  $        2,305  $        4,799  $        1,701  $        7,443
                                       ==============  ==============  ==============  ==============
NET INCOME PER SHARE -- BASIC AND
  DILUTED............................  $         0.12  $         0.24  $         0.09  $         0.44
                                       ==============  ==============  ==============  ==============
SHARES USED IN COMPUTING NET INCOME
  PER SHARE --
  BASIC AND DILUTED..................      18,870,580      19,608,607      18,768,758      16,935,596
</TABLE>

  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       3
<PAGE>
                     HORIZON OFFSHORE, INC. AND SUBSIDIARIES
                      CONSOLIDATED STATEMENTS OF CASH FLOWS
                                  (UNAUDITED)
                                 (IN THOUSANDS)


                                          SIX MONTHS ENDED
                                              JUNE 30,
                                       ----------------------
                                          1999        1998
                                       ----------  ----------
CASH FLOW FROM OPERATING ACTIVITIES:
  Net income ........................  $    1,701  $    7,443
  Adjustments to reconcile net income
     to net cash provided by
     operating activities --
     Depreciation and amortization...       3,361       1,515
     Deferred income taxes...........         867       1,102
     Changes in operating assets and
      liabilities --
       Accounts receivable...........       8,844      (9,491)
       Costs in excess of billings...      (4,637)    (17,256)
       Billings in excess of costs...      (1,030)        408
       Other current assets..........          24        (458)
       Accounts payable..............      (4,448)       (305)
       Accrued liabilities...........      (1,504)      9,398
       Accrued job costs.............        (172)     12,534
       Accrued interest..............          --        (673)
       Due to related parties........          12          --
       Income taxes payable..........          --         511
                                       ----------  ----------
          Net cash provided by
             operating activities....       3,018       4,728
CASH FLOW FROM INVESTING ACTIVITIES:
  Purchases and additions to
     equipment.......................     (15,240)    (55,768)
  Drydock costs......................      (4,060)       (601)
  Purchase of other assets...........        (250)         96
                                       ----------  ----------
          Net cash used in investing
             activities..............     (19,550)    (56,273)
CASH FLOW FROM FINANCING ACTIVITIES:
  Borrowings under notes payable and
     long-term debt..................      18,800      13,954
  Loan fees..........................          --        (792)
  Principal payments on long-term
     debt............................      (4,258)    (24,232)
  Issuance of common stock...........          --         950
  Initial public offering proceeds,
     net.............................          --      68,814
  Purchase of treasury stock.........         (18)         --
                                       ----------  ----------
          Net cash provided by
             financing activities....      14,524      58,694
                                       ----------  ----------
NET INCREASE (DECREASE) IN CASH AND
  CASH EQUIVALENTS...................      (2,008)      7,149
CASH AND CASH EQUIVALENTS AT
  BEGINNING OF PERIOD................       9,649       2,846
                                       ----------  ----------
CASH AND CASH EQUIVALENTS AT END OF
  PERIOD.............................  $    7,641  $    9,995
                                       ==========  ==========
SUPPLEMENTAL DISCLOSURES:
  Cash paid for interest.............  $    2,967  $    1,914
  Cash paid for income taxes.........  $       --  $      265
  Non-cash investing and financing
     activities:
     Purchase and additions to
      equipment with the issuance of
      notes payable..................  $       --  $   24,097
     Purchase and additions to
      equipment with the issuance of
      treasury stock.................  $      998  $       --


  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       4

<PAGE>
                                   SIGNATURE

     PURSUANT TO THE REQUIREMENTS OF THE SECURITIES EXCHANGE ACT OF 1934, THE
REGISTRANT HAS DULY CAUSED THIS REPORT TO BE SIGNED ON ITS BEHALF BY THE
UNDERSIGNED THEREUNTO DULY AUTHORIZED.

                                          HORIZON OFFSHORE, INC.

                                         By: /s/DAVID W. SHARP
                                                DAVID W. SHARP
                                                EXECUTIVE VICE PRESIDENT AND
                                                  CHIEF FINANCIAL OFFICER

Date:  August 25, 1999

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