<PAGE>

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

                                   FORM 10-Q

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

                For the quarterly period ended  MARCH 31, 2001
                                              ------------------

                                      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 0-22258

                             AVIVA PETROLEUM INC.
            (Exact name of registrant as specified in its charter)

Texas                                                           75-1432205
(State or other jurisdiction of                                 (I.R.S. Employer
incorporation or organization)                                  Identification
                                                                Number)

8235 Douglas Avenue,                                            75225
Suite 400, Dallas, Texas                                        (Zip Code)
(Address of principal executive offices)

                                (214) 691-3464
             (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
                                                               --       ---

Number of shares of Common Stock, no par value, outstanding at March 31, 2001,
was 46,900,132 of which 27,717,775 shares of Common Stock were represented by
Depositary Shares. Each Depositary Share represents five shares of Common Stock
held by a Depositary.
<PAGE>

PART I - FINANCIAL INFORMATION

Item 1. Financial Statements.
----------------------------

                     AVIVA PETROLEUM INC. AND SUBSIDIARIES
                     Condensed Consolidated Balance Sheet
                    (in thousands, except number of shares)
                                   (unaudited)

<TABLE>
<CAPTION>
                                                                      March 31,          December 31,
                                                                          2001                  2000
                                                                 -------------         -------------
<S>                                                              <C>                   <C>
ASSETS

Current assets:
    Cash and cash equivalents                                    $         623         $         820
    Accounts receivable                                                    359                   237
    Inventories                                                            156                   161
    Prepaid expenses and other                                             159                   187
                                                                 -------------         -------------
       Total current assets                                              1,297                 1,405
                                                                 -------------         -------------

Property and equipment, at cost (note 2):

    Oil and gas properties and equipment (full cost method)             16,457                16,414
    Other                                                                  337                   333
                                                                 -------------         -------------
                                                                        16,794                16,747
       Less accumulated depreciation, depletion
          and amortization                                             (15,857)              (15,791)
                                                                 -------------         -------------
                                                                           937                   956
Other assets                                                             1,011                   950
                                                                 -------------         -------------
                                                                 $       3,245         $       3,311
                                                                 =============         =============
LIABILITIES AND STOCKHOLDERS' EQUITY

Current liabilities:
    Accounts payable                                             $         645         $         945
    Accrued liabilities                                                    117                   115
                                                                 -------------         -------------
       Total current liabilities                                           762                 1,060
                                                                 -------------         -------------

Gas balancing obligations and other                                        378                   375

Stockholders' equity:
    Common stock, no par value, authorized 348,500,000 shares;
       issued 46,900,132 shares                                          2,345                 2,345
    Additional paid-in capital                                          37,710                37,710
    Accumulated deficit*                                               (37,950)              (38,179)
                                                                 -------------         -------------
       Total stockholders' equity                                        2,105                 1,876

Commitments and contingencies (note 3)
                                                                 -------------         -------------
                                                                 $       3,245         $       3,311
                                                                 =============         =============
</TABLE>

* Accumulated deficit of $70,057 was eliminated at December 31, 1992 in
connection with a quasi-reorganization.

See accompanying notes to condensed consolidated financial statements.

                                       2
<PAGE>

                     AVIVA PETROLEUM INC. AND SUBSIDIARIES
                Condensed Consolidated Statement of Operations
                     (in thousands, except per share data)
                                  (unaudited)

<TABLE>
<CAPTION>
                                                                                      Three Months Ended
                                                                                            March 31,
                                                                                    2001                  2000
                                                                                ------------         -------------
<S>                                                                             <C>                  <C>
Revenue:
    Oil and gas sales                                                           $        600         $       2,541
    Services fee                                                                         166                     -
                                                                                ------------         -------------
       Total revenue                                                                     766                 2,541
                                                                                ------------         -------------

Expense:
    Production                                                                           358                   810
    Depreciation, depletion and amortization                                              67                   235
    General and administrative                                                           289                   301
    Recovery of losses on accounts receivable                                            (25)                  (52)
                                                                                ------------         -------------

       Total expense                                                                     689                 1,294
                                                                                ------------         -------------

Other income (expense):
    Interest and other income (expense), net                                             170                     -
    Interest expense                                                                      (1)                 (395)
                                                                                ------------         -------------

       Total other income (expense)                                                      169                  (395)
                                                                                ------------         -------------

Earnings before income taxes                                                             246                   852

Income taxes                                                                              17                   119
                                                                                ------------         -------------

          Net earnings                                                          $        229         $         733
                                                                                ============         =============


Weighted average common shares outstanding                                            46,900                46,900
                                                                                ============         =============

Basic and diluted net earnings per common share                                 $       0.00         $        0.02
                                                                                ============         =============
</TABLE>


See accompanying notes to condensed consolidated financial statements.

                                       3
<PAGE>

                     AVIVA PETROLEUM INC. AND SUBSIDIARIES
                Condensed Consolidated Statement of Cash Flows
                                (in thousands)
                                  (unaudited)

<TABLE>
<CAPTION>
                                                                                               Three Months Ended
                                                                                                   March 31,
                                                                                               2001                  2000
                                                                                      -------------         -------------
<S>                                                                                   <C>                   <C>
Net earnings                                                                          $         229         $         733
Adjustments to reconcile net earnings to net cash
   provided by (used in) operating activities:
    Depreciation, depletion and amortization                                                     67                   235
    Changes in working capital and other                                                       (420)                 (693)
                                                                                      -------------         -------------

       Net cash provided by (used in) operating activities                                     (124)                  275
                                                                                      -------------         -------------

Cash flows from investing activities:

    Property and equipment expenditures                                                         (86)                 (260)
    Proceeds from sale of assets                                                                  4                     -
                                                                                      -------------         -------------

       Net cash used in investing activities                                                    (82)                 (260)
                                                                                      -------------         -------------

Cash flows from financing activities                                                              -                     -
                                                                                      -------------         -------------

Effect of exchange rate changes on cash and
    cash equivalents                                                                              9                     2
                                                                                      -------------         -------------

Net increase (decrease) in cash and cash equivalents                                           (197)                   17
Cash and cash equivalents at beginning of the period                                            820                   846
                                                                                      -------------         -------------

Cash and cash equivalents at end of the period                                        $         623         $         863
                                                                                      =============         =============
</TABLE>

See accompanying notes to condensed consolidated financial statements.

                                       4
<PAGE>

                     AVIVA PETROLEUM INC. AND SUBSIDIARIES
           Condensed Consolidated Statement of Stockholders' Equity
                    (in thousands, except number of shares)
                                  (unaudited)

<TABLE>
<CAPTION>
                                                         Common Stock
                                            -------------------------------
                                                                                   Additional                             Total
                                                    Number                            Paid-in     Accumulated     Stockholders'
                                                 of Shares           Amount           Capital         Deficit            Equity
                                            --------------    -------------     -------------  --------------     -------------
<S>                                         <C>               <C>               <C>            <C>                <C>
Balances at December 31, 2000                   46,900,132    $       2,345     $      37,710  $      (38,179)    $       1,876
Net earnings                                             -                -                 -             229               229
                                            --------------    -------------     -------------  --------------     -------------

Balances at March 31, 2001                      46,900,132    $       2,345     $      37,710  $      (37,950)    $       2,105
                                            ==============    =============     =============  ==============     =============
</TABLE>


See accompanying notes to condensed consolidated financial statements.

                                       5
<PAGE>

                     AVIVA PETROLEUM INC. AND SUBSIDIARIES
             Notes to Condensed Consolidated Financial Statements
                                  (unaudited)

1.   General

     The condensed consolidated financial statements of Aviva Petroleum Inc. and
     subsidiaries (the "Company" or "Aviva") included herein have been prepared
     by the Company without audit, pursuant to the rules and regulations of the
     Securities and Exchange Commission. Certain information and footnote
     disclosures normally included in financial statements prepared in
     accordance with generally accepted accounting principles have been
     condensed or omitted pursuant to such rules and regulations, although the
     Company believes that the disclosures contained herein are adequate to make
     the information presented not misleading. These condensed consolidated
     financial statements should be read in conjunction with the Company's prior
     audited yearly financial statements and the notes thereto, included in the
     Company's latest annual report on Form 10-K.

     In the opinion of the Company, all adjustments, consisting of normal
     recurring accruals, necessary to present fairly the information in the
     accompanying financial statements have been included. The results of
     operations for such interim periods are not necessarily indicative of the
     results for the full year.

2.   Property and Equipment

     Internal general and administrative costs directly associated with oil and
     gas property acquisition, exploration and development activities have been
     capitalized in accordance with the accounting policies of the Company. Such
     costs totaled $20,000 for the three months ended March 31, 2001 and $15,000
     for the three months ended March 31, 2000.

     Unevaluated oil and gas properties totaling $273,000 and $272,000 at March
     31, 2001 and December 31, 2000, respectively, have been excluded from costs
     subject to depletion. The Company capitalized interest costs of $16,000 for
     the three-month period ended March 31, 2000 on these properties.

3.   Commitments and Contingencies

     The Company is engaged in ongoing operations on the Santana contract in
     Colombia. The contract obligations have been met; however, the Company
     plans to recomplete certain existing wells and engage in various other
     projects. The Company's current share of the estimated future costs of
     these activities is approximately $0.3 million at March 31, 2001. Any
     substantial increase in the amount of the above referenced expenditures
     could adversely affect the Company's ability to meet these obligations.

     The Company expects to fund these activities using existing cash and cash
     provided from operations. Risks that could adversely affect funding of such
     activities include, among others, delays in obtaining any required
     environmental approvals and permits, cost overruns, failure to produce the
     reserves as projected or a decline in the sales price of oil. Depending on
     the results of future exploration and development activities, substantial
     expenditures which have not been included in the Company's cash flow
     projections may be required. Failure to fund certain expenditures could
     result in a decrease in the Company's ownership interest in Argosy.

                                       6
<PAGE>

                     AVIVA PETROLEUM INC. AND SUBSIDIARIES
             Notes to Condensed Consolidated Financial Statements
                            (unaudited) (continued)

On August 3, 1998, leftist Colombian guerrillas inflicted significant damage on
the Company's oil processing and storage facilities at the Mary field, and to a
lesser extent, at the Linda facilities. Since that time the Company has been
subject to lesser attacks on its pipelines and equipment resulting in only minor
interruptions of oil sales. The Colombian army guards the Company's operations;
however, there can be no assurance that the Company's operations will not be the
target of additional guerrilla attacks in the future. The damages resulting from
the above referenced attacks were covered by insurance. There can be no
assurance that such coverage will remain available or affordable.

Under the terms of the contracts with Ecopetrol, a minimum of 25% of all
revenues from oil sold to Ecopetrol is paid in Colombian pesos which may only be
utilized in Colombia. To date, the Company has experienced no difficulty in
repatriating the remaining 75% of such payments, which are payable in U.S.
dollars.

Activities of the Company with respect to the exploration, development and
production of oil and natural gas are subject to stringent foreign, federal,
state and local environmental laws and regulations, including but not limited to
the Oil Pollution Act of 1990, the Outer Continental Shelf Lands Act, the
Federal Water Pollution Control Act, the Resource Conservation and Recovery Act
and the Comprehensive Environmental Response, Compensation, and Liability Act.
Such laws and regulations have increased the cost of planning, designing,
drilling, operating and abandoning wells. In most instances, the statutory and
regulatory requirements relate to air and water pollution control procedures and
the handling and disposal of drilling and production wastes. Although the
Company believes that compliance with environmental laws and regulations will
not have a material adverse effect on the Company's future operations or
earnings, risks of substantial costs and liabilities are inherent in oil and gas
operations and there can be no assurance that significant costs and liabilities,
including civil or criminal penalties for violations of environmental laws and
regulations, will not be incurred. Moreover, it is possible that other
developments, such as stricter environmental laws and regulations or claims for
damages to property or persons resulting from the Company's operations, could
result in substantial costs and liabilities. For additional discussions on the
applicability of environmental laws and regulations and other risks that may
affect the Company's operations, see the Company's latest annual report on Form
10-K.

The Company is involved in certain litigation involving its oil and gas
activities. Management of the Company believes that these litigation matters
will not have any material adverse effect on the Company's financial condition
or results of operations.

                                       7
<PAGE>

                     AVIVA PETROLEUM INC. AND SUBSIDIARIES
             Notes to Condensed Consolidated Financial Statements
                            (unaudited) (continued)

4.   Segment Information

     The following is a summary of segment information of the Company as of and
     for the three-month periods ended March 31, 2001 and 2000 (in thousands):

<TABLE>
<CAPTION>
                                                                      United
                                                                      States              Colombia                 Total
                                                                ------------          ------------          ------------
     <S>                                                        <C>                   <C>                   <C>
     2001
     ----
     Revenue:

       Oil and gas sales                                        $        286          $        314          $        600
       Service fees                                                      166                     -                   166
                                                                ------------          ------------          ------------
                                                                         452                   314                   766
                                                                ------------          ------------          ------------
     Expense:
       Production                                                        214                   144                   358
       Depreciation, depletion and amortization                           37                    30                    67
       General and administrative                                        268                    21                   289
       Recovery of losses on accounts receivable                         (25)                    -                   (25)
                                                                ------------          ------------          ------------
                                                                         494                   195                   689
                                                                ------------          ------------          ------------

     Interest and other income (expense), net                             18                   152                   170
     Interest expense                                                     (1)                    -                    (1)
                                                                ------------          ------------          ------------

     Earnings (loss) before income taxes                                 (25)                  271                   246
     Income taxes                                                          -                   (17)                  (17)
                                                                ------------          ------------          ------------

     Net earnings (loss)                                        $        (25)         $        254          $        229
                                                                ============          ============          ============

     Total assets                                               $      1,705          $      1,540          $      3,245
                                                                ============          ============          ============


     2000
     ----
     Oil and gas sales                                          $        397          $      2,144          $      2,541
                                                                ------------          ------------          ------------

     Expense:
       Production                                                        262                   548                   810
       Depreciation, depletion and amortization                           39                   196                   235
       General and administrative                                        290                    11                   301
       Recovery of losses on accounts receivable                         (52)                    -                   (52)
                                                                ------------          ------------          ------------
                                                                         539                   755                 1,294
                                                                ------------          ------------          ------------

     Interest and other income (expense), net                             11                   (11)                    -
     Interest expense                                                   (114)                 (281)                 (395)
                                                                ------------          ------------          ------------

     Earnings (loss) before income taxes                                (245)                1,097                   852
     Income taxes                                                          -                   119                   119
                                                                ------------          ------------          ------------

     Net earnings (loss)                                        $       (245)         $        978          $        733
                                                                ============          ============          ============

     Total assets                                               $      2,217          $      7,630          $      9,847
                                                                ============          ============          ============
</TABLE>

                                       8
<PAGE>

Item 2. Management's Discussion and Analysis of Financial Condition and
-----------------------------------------------------------------------
Results of Operations.
---------------------

Results of Operations
---------------------

Three Months Ended March 31, 2001 compared to Three Months Ended March 31, 2000
-------------------------------------------------------------------------------

<TABLE>
<CAPTION>
                                                               United States                Colombia
                                                           Oil               Gas              Oil             Total
                                                     -------------     -------------    -------------     -------------
              (Thousands)
              <S>                                    <C>               <C>              <C>               <C>
              Oil and gas sales - 2000               $         378     $          19    $       2,144     $       2,541

              Volume variance                                 (120)               (9)          (1,739)           (1,868)
              Price variance                                    (8)               26              (91)              (73)
                                                     -------------     -------------    -------------     -------------

              Oil and gas sales - 2001               $         250     $          36    $         314     $         600
                                                     =============     =============    =============     =============
</TABLE>

Colombian oil volumes were 14,000 barrels in the first quarter of 2001, a
decrease of 62,000 barrels as compared to the first quarter of 2000. Such
decrease is due to a 50,000 barrel decrease resulting from the transfer of
partnership interests to Crosby Capital L.L.C. ("Crosby") and a 12,000 barrel
decrease resulting from production declines. The transfer of partnership
interests to Crosby on June 8, 2000, was part of an overall restructuring plan
which eliminated all of the Company's long-term debt.

U.S. oil volumes were 9,000 barrels in 2001, down approximately 5,000 barrels
from 2000. Such decrease is due to the relinquishment of Main Pass 41 effective
November 7, 2000. U.S. gas volumes were 5,000 thousand cubic feet (MCF) in 2001,
down 2,000 MCF from 2000. Such decrease is due to the relinquishment of Main
Pass 41 and normal production declines.

Colombian oil prices averaged $21.83 per barrel during the first quarter of
2001. The average price for the same period of 2000 was $28.13 per barrel. The
Company's average U.S. oil price decreased to $26.80 per barrel in 2001, down
from $27.62 per barrel in 2000. In 2001 prices have been lower than in the first
quarter of 2000 due to a decrease in world oil prices. U.S. gas prices averaged
$6.77 per MCF in 2001 compared to $2.86 per MCF in 2000.

Service fees of $166,000 for administering the Colombian assets were received in
2001 pursuant to a Service Agreement with Crosby. This amount is net of Aviva
Overseas' 22.1196% share of the fee.

Operating costs decreased approximately 56%, or $452,000, primarily as a result
of the transfer of partnership interests to Crosby.

Depreciation, depletion and amortization decreased by 71%, or $168,000,
primarily as a result of the transfer of partnership interests to Crosby and a
decrease in the amount of oil produced.

Interest and other income increased $170,000 mainly due to a $119,000 gain on
the settlement of a disputed payable.

Interest expense decreased $394,000 in the first quarter of 2001, due to the
extinguishment of the Company's long-term debt in 2000.

Income taxes were $102,000 lower in 2001 principally as a result of the transfer
of partnership interests to Crosby.

                                       9
<PAGE>

New Accounting Pronouncements
-----------------------------

The Company has adopted SFAS No. 133, Accounting for Derivative Instruments and
Hedging Activities, as amended. This statement establishes accounting and
reporting standards for derivative instruments and hedging activities and
requires the Company to recognize all derivatives on its balance sheet at fair
value. If the derivative is a hedge, depending on the nature of the hedge,
changes in the fair value of the derivatives are either offset against the
change in fair value of the hedged item through earnings, or recognized in other
comprehensive income until the hedged item is recognized in earnings. As of
January 1, 2001, the date of adoption, and as of March 31, 2001 and the
three-month period then ended, the Company was not a party to any derivative
financial instruments.


Liquidity and Capital Resources
-------------------------------

Cash and cash equivalents totaled $623,000 and $820,000 at March 31, 2001 and
December 31, 2000, respectively. The decrease in cash and cash equivalents
resulted primarily from net cash used in operating activities ($124,000) and
property additions ($86,000).

Net cash used in operating activities was $(124,000) in 2001, compared to
$275,000 net cash provided by operating activities for 2000. This decrease
resulted primarily from the transfer of partnership interests to Crosby,
effective June 8, 2000, resulting in lower levels of net cash flow from
operations. Additionally, production declines and lower oil prices received for
the Company's Colombian oil production contributed to the decrease.

The Company plans to recomplete certain existing wells and engage in various
other projects in Colombia. The Company's current share of the estimated future
costs of these development activities is approximately $0.3 million at March 31,
2001. Any substantial increase in the amount of the above referenced
expenditures could adversely affect the Company's ability to meet these
obligations.

The Company expects to fund these activities using existing cash and cash
provided from operations. Risks that could adversely affect funding of such
activities include, among others, delays in obtaining any required environmental
permits, failure to produce the reserves as projected or a decline in the sales
price of oil. Any substantial increases in the amounts of these required
expenditures could adversely affect the Company's ability to fund these
activities. Depending on the results of future exploration and development
activities, substantial expenditures, which have not been included in the
Company's cash flow projections, may be required. Failure to fund certain
expenditures could result in a decrease in the Company's ownership interest in
Argosy. The outcome of these matters cannot be projected with certainty.

With the exception of historical information, the matters discussed in this
quarterly report contain forward-looking statements that involve risks and
uncertainties. Although the Company believes that its expectations are based on
reasonable assumptions, it can give no assurance that its goals will be
achieved. Important factors that could cause actual results to differ materially
from those in the forward-looking statements herein include, among other things,
general economic conditions, volatility of oil and gas prices, the impact of
possible geopolitical occurrences world-wide and in Colombia, imprecision of
reserve estimates, changes in laws and regulations, unforeseen engineering and
mechanical or technological difficulties in drilling, working-over and operating
wells during the periods covered by the forward-looking statements, as well as
other factors described in the Company's annual report on Form 10-K.

                                       10
<PAGE>

Item 3.  Quantitative and Qualitative Disclosures About Market Risk
-------------------------------------------------------------------

The Company is exposed to market risk from changes in commodity prices. The
Company produces and sells crude oil and natural gas. These commodities are sold
based on market prices established with the buyers. The Company does not use
financial instruments to hedge commodity prices.

PART II - OTHER INFORMATION

Item 6.  Exhibits and Reports on Form 8-K
-----------------------------------------

a) Exhibits
-----------

None

b) Reports on Form 8-K
----------------------

The Company did not file any Current Reports on Form 8-K during or subsequent to
the end of the first quarter of 2001.

                                       11
<PAGE>

                                  SIGNATURES

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.

                                         AVIVA PETROLEUM INC.



Date:  May 9, 2001                       /s/ Ronald Suttill
                                         ---------------------------
                                         Ronald Suttill
                                         President and Chief Executive Officer

                                         /s/  James L. Busby
                                         ---------------------------
                                         James L. Busby
                                         Secretary, Treasurer and Chief
                                         Financial Officer
                                         (Principal Financial and Accounting
                                         Officer)

                                       12
<PAGE>

                                INDEX TO EXHIBITS

Exhibit
Number            Description of Exhibit
------            ----------------------

None

                                       13