<PAGE>

-------------------------------------------------------------------------------
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                      SECURITIES AND EXCHANGE COMMISSION
                           Washington, D.C.  20549

                                  FORM 10-Q

          [x]  QUARTERLY REPORT UNDER SECTION 13 OR 15(d) OF THE 
                      SECURITIES EXCHANGE ACT OF 1934
   
                 For the quarterly period ended March 31, 1999

                                      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 0-9408 

                           PRIMA ENERGY CORPORATION
            (Exact name of Registrant as specified in its charter)
        
                DELAWARE                                84-1097578
    (State or other jurisdiction of        (I.R.S. Employer Identification No.)
     incorporation or organization)
                                       
                  1801 BROADWAY, SUITE 500, DENVER CO 80202
            (Address of principal executive offices)   (Zip Code)
                                       
                               (303) 297-2100
             (Registrant's telephone number, including area code)

                                  NO CHANGE
             (Former name, former address and former fiscal year, 
                        if changed from last report.)


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 [  ] 

As of April 30, 1999, the Registrant had 5,673,429 shares of Common Stock, 
$0.015 Par Value, outstanding.

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<PAGE>

                                       
                           PRIMA ENERGY CORPORATION


                                     INDEX

<TABLE>
    PART I - FINANCIAL INFORMATION                                                                   Page
                                                                                                     ----
<S>                                                                                                  <C>
         Item 1.   Financial Statements

              Unaudited consolidated balance sheets . . . . . . . . . . . . . . . . . . . . . . . .    3

              Unaudited consolidated statements of income . . . . . . . . . . . . . . . . . . . . .    5

              Unaudited consolidated statements of comprehensive income . . . . . . . . . . . . . .    6

              Unaudited consolidated statements of cash flows . . . . . . . . . . . . . . . . . . .    7

              Notes to unaudited consolidated financial statements . . . . . . . . . . . . . . . . .   8

         Item 2.   Management's Discussion and Analysis of
                   Financial Condition and Results of Operations . . . . . . . . . . . . . . . . . .  11
      
         Item 3.   Quantitative and Qualitative Disclosures
                   About Market Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  15

         Cautionary Statement for Purposes of the "Safe Harbor" Provisions of the
             Private Securities Litigation Reform Act of 1995. . . . . . . . . . . . . . . . . . . .  17


    PART II - OTHER INFORMATION


         Item 6.  Exhibits and Reports on Form 8-K . . . . . . . . . . . . . . . . . . . . . . . . .  17

         Signatures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  18
</TABLE>

<PAGE>
                                       
                          PRIMA ENERGY CORPORATION 
                        CONSOLIDATED BALANCE SHEETS 
                                 (UNAUDITED)

<TABLE>
<CAPTION>
                              ASSETS

                                                                            MARCH 31,      DECEMBER 31,
                                                                              1999             1998   
                                                                          ------------     ------------
<S>                                                                       <C>              <C>
CURRENT ASSETS
Cash and cash equivalents.............................................    $    996,000     $  2,522,000 
Cash held in like-kind exchange escrow................................      25,951,000                0
Available for sale securities, at market..............................       2,279,000        2,391,000 
Receivables (net of allowance for doubtful
  accounts: 3/31/99, $47,000; 12/31/98, $47,000)......................       3,667,000        4,696,000 
Tubular goods inventory...............................................         548,000          612,000 
Other.................................................................         195,000          452,000 
                                                                          ------------     ------------

      Total current assets............................................      33,636,000       10,673,000 
                                                                          ------------     ------------

OIL AND GAS PROPERTIES, at cost, accounted
  for using the full cost method......................................      63,491,000       86,081,000
Less accumulated depreciation,
  depletion and amortization..........................................     (34,277,000)     (33,135,000)
                                                                          ------------     ------------

      Oil and gas properties - net....................................      29,214,000       52,946,000 
                                                                          ------------     ------------

PROPERTY AND EQUIPMENT, at cost
Oilfield service equipment............................................       5,271,000        4,353,000 
Furniture and equipment...............................................         829,000          815,000 
Field office, shop and land...........................................         455,000          439,000
                                                                          ------------     ------------
                                                                             6,555,000        5,607,000 
Less accumulated depreciation.........................................      (3,114,000)      (2,946,000)
                                                                          ------------     ------------

      Property and equipment - net....................................       3,441,000        2,661,000 
                                                                          ------------     ------------

OTHER ASSETS..........................................................         257,000          586,000 
                                                                          ------------     ------------

                                                                          $ 66,548,000     $ 66,866,000 
                                                                          ------------     ------------
                                                                          ------------     ------------
</TABLE>


See accompanying notes to unaudited consolidated financial statements.

                                       3
<PAGE>

                           PRIMA ENERGY CORPORATION
                     CONSOLIDATED BALANCE SHEETS (cont'd.)
                                  (UNAUDITED)

               LIABILITIES AND STOCKHOLDERS' EQUITY

<TABLE>
<CAPTION>
                                                                    MARCH 31,        DECEMBER 31,
                                                                      1999              1998     
                                                                   -----------       -----------
<S>                                                                <C>               <C>
CURRENT LIABILITIES
Accounts payable................................................   $   892,000       $ 2,122,000
Amounts payable to oil and gas property owners..................       822,000           973,000
Ad valorem and production taxes payable.........................     1,489,000         1,552,000
Accrued and other liabilities...................................       616,000           439,000
Current portion of notes payable................................       304,000           120,000
                                                                   -----------       -----------

      Total current liabilities.................................     4,123,000         5,206,000

NOTE PAYABLE....................................................       120,000           120,000
AD VALOREM TAXES, non-current...................................     1,464,000         1,088,000
DEFERRED TAX LIABILITY..........................................     9,346,000         9,144,000
                                                                   -----------       -----------

      Total liabilities.........................................    15,053,000        15,558,000
                                                                   -----------       -----------


STOCKHOLDERS' EQUITY
Preferred stock, $0.001 par value, 2,000,000 shares
  authorized; no shares issued or outstanding...................             0                 0
Common stock, $0.015 par value, 12,000,000 shares
  authorized; 5,835,556 shares issued...........................        87,000            87,000
Additional paid-in capital......................................     4,417,000         4,417,000
Retained earnings...............................................    49,065,000        47,550,000
Accumulated other comprehensive income (loss)...................       (37,000)           51,000 
Treasury stock, 158,987 and 63,787 shares at cost...............    (2,037,000)         (797,000)
                                                                   -----------       -----------

      Total stockholders' equity................................    51,495,000        51,308,000
                                                                   -----------       -----------

                                                                   $66,548,000       $66,866,000
                                                                   -----------       -----------
                                                                   -----------       -----------
</TABLE>


     See accompanying notes to unaudited consolidated financial statements.

                                       4
<PAGE>

                            PRIMA ENERGY CORPORATION
                       CONSOLIDATED STATEMENTS OF INCOME
                                  (UNAUDITED)

<TABLE>
<CAPTION>
                                                               THREE MONTHS ENDED
                                                                    MARCH 31,         
                                                           --------------------------
                                                              1999            1998    
                                                           ----------     -----------
<S>                                                        <C>            <C>
REVENUES
Oil and gas sales.......................................   $3,826,000     $ 4,150,000 
Trading revenues........................................      417,000       1,649,000 
Oilfield services.......................................    1,032,000       1,128,000 
Management and operator fees............................      240,000         252,000 
Interest and dividend income............................      274,000         134,000 
Settlement income and other.............................            0       3,865,000 
                                                           ----------     -----------
                                                            5,789,000      11,178,000 
                                                           ----------     -----------

EXPENSES
Depreciation, depletion and amortization................    1,309,000       1,505,000
Lease operating expense.................................      493,000         504,000 
Production taxes........................................      302,000         345,000 
Cost of trading.........................................      354,000       1,410,000
Cost of oilfield services...............................      667,000         864,000 
General and administrative..............................      574,000         521,000 
                                                           ----------     -----------
                                                            3,699,000       5,149,000 
                                                           ----------     -----------

INCOME BEFORE INCOME TAXES..............................    2,090,000       6,029,000 
PROVISION FOR INCOME TAXES..............................      575,000       1,890,000 
                                                           ----------     -----------

NET INCOME..............................................   $1,515,000     $ 4,139,000 
                                                           ----------     -----------
                                                           ----------     -----------


BASIC NET INCOME PER SHARE..............................   $     0.26     $      0.72 
                                                           ----------     -----------
                                                           ----------     -----------
DILUTED NET INCOME PER SHARE............................   $     0.26     $      0.70 
                                                           ----------     -----------
                                                           ----------     -----------

WEIGHTED AVERAGE COMMON SHARES
  OUTSTANDING...........................................    5,745,186       5,770,250
                                                           ----------     -----------
                                                           ----------     -----------
WEIGHTED AVERAGE COMMON SHARES
  OUTSTANDING ASSUMING DILUTION.........................    5,832,440       5,893,829 
                                                           ----------     -----------
                                                           ----------     -----------
</TABLE>


     See accompanying notes to unaudited consolidated financial statements.

                                       5
<PAGE>

                           PRIMA ENERGY CORPORATION 
                CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
                                  (UNAUDITED)

<TABLE>
<CAPTION>
                                                                       THREE MONTHS ENDED
                                                                            MARCH 31,                 
                                                                     -----------------------
                                                                        1999         1998    
                                                                     ----------   ----------
<S>                                                                  <C>          <C>
Net income........................................................   $1,515,000   $4,139,000 
                                                                     ----------   ----------

Other comprehensive income:

Unrealized gain (loss) on available-for-sale securities...........     (140,000)       3,000
Deferred income tax expense related to unrealized
 gain on available-for-sale securities............................       52,000       (1,000)
                                                                     ----------   ----------

                                                                        (88,000)       2,000
                                                                     ----------   ----------

COMPREHENSIVE INCOME..............................................   $1,427,000   $4,141,000
                                                                     ----------   ----------
                                                                     ----------   ----------
</TABLE>



     See accompanying notes to unaudited consolidated financial statements.

                                       6
<PAGE>

                           PRIMA ENERGY CORPORATION
                     CONSOLIDATED STATEMENTS OF CASH FLOWS
                                  (UNAUDITED)

<TABLE>
<CAPTION>
                                                                               THREE MONTHS ENDED
                                                                                    MARCH 31,
                                                                          ---------------------------
                                                                             1999             1998
                                                                          ------------    -----------
<S>                                                                       <C>             <C>
OPERATING ACTIVITIES
Net income ...........................................................    $  1,515,000    $ 4,139,000 
Adjustments to reconcile net income to net cash
 provided by operating activities:
   Depreciation, depletion and amortization...........................       1,309,000      1,505,000
   Deferred income taxes..............................................         254,000      1,552,000
   Other..............................................................         376,000        338,000 
   Changes in current assets and liabilities:
     Receivables......................................................       1,029,000      1,355,000 
     Inventory........................................................          64,000         16,000 
     Other current assets.............................................         257,000         64,000 
     Payables.........................................................      (1,444,000)    (2,128,000)
     Accrued and other liabilities....................................         176,000        183,000 
                                                                          ------------    -----------
       Net cash provided by operating activities......................       3,536,000      7,024,000 
                                                                          ------------    -----------

INVESTING ACTIVITIES
Additions to oil and gas properties...................................      (3,361,000)    (2,699,000)
Purchases of other property...........................................        (763,000)      (178,000)
Purchases of available for sale securities............................         (28,000)       (28,000)
Proceeds from sales of oil & gas and other property...................      26,281,000         15,000
Increase in cash held in like-kind exchange escrow....................     (25,951,000)             0 
                                                                          ------------    -----------
       Net cash used in investing activities..........................      (3,822,000)    (2,890,000)
                                                                          ------------    -----------

FINANCING ACTIVITIES
Treasury stock purchased..............................................      (1,240,000)             0
Proceeds from issuance of common stock................................               0         23,000
                                                                          ------------    -----------
       Net cash provided by (used in) financing activities............      (1,240,000)        23,000
                                                                          ------------    -----------

INCREASE (DECREASE) IN CASH
  AND CASH EQUIVALENTS................................................      (1,526,000)     4,157,000 
CASH AND CASH EQUIVALENTS, beginning of period........................       2,522,000      5,644,000 
                                                                          ------------    -----------

CASH AND CASH EQUIVALENTS, end of period..............................    $    996,000    $ 9,801,000
                                                                          ------------    -----------
                                                                          ------------    -----------

Supplemental schedule of noncash investing and financing activities:
        The Company purchased oilfield service assets in March 1999.  A summary of the transaction is
as follows:

Fair value of assets acquired.........................................    $    460,000
Cash paid.............................................................         276,000
                                                                          ------------
Note payable issued to seller.........................................    $    184,000
                                                                          ------------
                                                                          ------------
</TABLE>

     See accompanying notes to unaudited consolidated financial statements.

                                       7
<PAGE>

                           PRIMA ENERGY CORPORATION
             NOTES TO UNAUDITED CONSOLIDATED FINANCIAL STATEMENTS


1.  GENERAL

    The financial information contained herein is unaudited but includes all 
adjustments (consisting of only normal recurring accruals) which, in the 
opinion of management, are necessary to present fairly the information set 
forth.  The  consolidated financial statements should be read in conjunction 
with the Notes to Consolidated Financial Statements which are included in the 
Annual Report on Form 10-K of Prima Energy Corporation for the year ended 
December 31, 1998.

    The results for interim periods are not necessarily indicative of results 
to be expected for the fiscal year of the Company ending December 31, 1999.  
The Company believes that the three month report filed on Form 10-Q is 
representative of its financial position, its results of operations and its 
cash flows for the periods ended March 31, 1999 and 1998.

2.  BASIS OF PRESENTATION

    The accompanying consolidated financial statements include the accounts 
of Prima Energy Corporation  and its subsidiaries, herein collectively 
referred to as "Prima" or the "Company."  All significant intercompany 
transactions have been eliminated.  Certain amounts in prior years have been 
reclassified to conform with the classifications at March 31, 1999.

3.  NOTES PAYABLE AND LINE OF CREDIT

    The Company's notes payable consist of the following:

<TABLE>
<CAPTION>
                                                          March 31,   December 31,
                                                            1999          1998       
                                                          ---------   ------------
<S>                                                       <C>         <C>
          Total.......................................    $424,000      $240,000
          Less, current portion.......................     304,000       120,000
                                                          --------      --------
          Long term...................................    $120,000      $120,000
                                                          --------      --------
                                                          --------      --------
</TABLE>

    The Company has two notes payable at March 31, 1999.  The first note is 
dated June 10, 1997 and is due on June 10, 2000.  Payments of principal and 
accrued interest (8% per annum) are to be made in three equal annual 
installments on the anniversary date of the note.  The note financed the 
purchase of oilfield service equipment by Action Oilfield Services, Inc., a 
wholly owned subsidiary.  The note balance was $240,000 at March 31, 1999.

    The second note is for $184,000.  It is dated March 10, 1999 and is due 
in one annual installment of principal and accrued interest (8% per annum) on 
March 10, 2000.  The note financed the purchase of oilfield service equipment 
by Action Energy Services, a newly formed wholly owned subsidiary.

                                       8
<PAGE>

    Prima maintains an $8,000,000 unsecured line of credit with a commercial 
bank.  The line of credit, which matures on May 1, 2001, bears interest at 
the bank's prime rate (7.75% at March 31, 1999), with interest payable 
monthly.  At December 31, 1998 and March 31, 1999, there were no amounts 
outstanding under the line of credit.

4.  HEDGING ACTIVITIES

    The Company's marketing and trading activities consist of marketing the 
Company's own production, marketing the production of others from wells 
operated by the Company, and natural gas trading activities that consist of 
the purchase and resale of natural gas.  Crude oil and natural gas futures, 
options and swaps are used from time to time in order to hedge the price of a 
portion of the Company's production, as well as to hedge the margins on 
natural gas purchased for resale. This is done to mitigate the risk of 
fluctuating oil and natural gas prices which can adversely affect operating 
results.  These transactions have been entered into with major financial 
institutions, thereby minimizing credit risk.  The Company did not hedge any 
of its oil production in the first quarters of 1999 or 1998, and hedged 
approximately 21% and 51% of its natural gas production in these same 
periods.  Hedging gains and losses were $55,000 and $(126,000) for the 
quarters ended March 31, 1999 and 1998, respectively, and were included in 
oil and  gas revenues at the time the hedged volumes were sold.  At March 31, 
1999, the Company had open oil futures contracts for May 1999 (10,000 
barrels) and June 1999 (10,000 barrels), with unrealized  losses of $10,000 
and $11,000, respectively.

    During June 1998, the Financial Accounting Standards Board issued 
Statement of Financial Accounting Standards No. 133 "Accounting for 
Derivative Instruments and Hedging Activities" ("SFAS 133").  SFAS 133 
establishes standards for derivative instruments, including certain 
derivative instruments embedded in other contracts (collectively referred to 
as derivatives) and for hedging activities.  SFAS 133 requires that an entity 
recognize all derivatives as either assets or liabilities in the statement of 
financial position and measure those instruments at fair value.  The 
accounting for changes in the fair value of a derivative (gains and losses) 
depends on the intended use of the derivative and the resulting designation.  
The Company is required to adopt SFAS 133 on January 1, 2000.  The Company 
has not completed the process of evaluating the impact that will result from 
adopting SFAS 133. 

5.  EARNINGS PER SHARE

    Basic net income per share is computed by dividing net income by the 
weighted average common shares outstanding during the period.  Diluted net 
income per share includes the potential dilution that could occur upon 
exercise of options to acquire common stock, computed using the treasury 
stock method.  The treasury stock method assumes that the increase in the 
number of shares issued is reduced by the number of shares which could have 
been repurchased by the Company with the proceeds from the exercise of the 
options (which were assumed to have been at the average market price of the 
common shares during the reporting period).

                                       9
<PAGE>

    The following table reconciles the numerator and denominator used in the 
calculation of basic and diluted net income per share.  

<TABLE>
<CAPTION>
                                                           Income         Shares       Per Share
                                                         (Numerator)   (Denominator)     Amount    
                                                         -----------   -------------   ----------
<S>                                                      <C>           <C>             <C>
Quarter Ended March 31, 1999:
     Basic Net Income per Share.........................  $1,515,000     5,745,186       $ 0.26
                                                                                         ------
                                                                                         ------
     Effect of Stock Options............................                    87,254    
                                                          ----------     ---------
     Diluted Net Income per Share.......................  $1,515,000     5,832,440       $ 0.26
                                                          ----------     ---------       ------
                                                          ----------     ---------       ------

Quarter Ended March 31, 1998:
     Basic Net Income per Share.........................  $4,139,000     5,770,250       $ 0.72
                                                                                         ------
                                                                                         ------
     Effect of Stock Options............................                   123,579     
                                                          ----------     ---------
     Diluted Net Income per Share.......................  $4,139,000     5,893,829       $ 0.70
                                                          ----------     ---------       ------
                                                          ----------     ---------       ------
</TABLE>

       During the quarter ended March 31, 1999, the Company repurchased 
95,200 shares for $1,240,000 as treasury stock pursuant to a stock repurchase 
program whereby the Board of Directors has authorized the repurchase of up to 
5% of the Company's common stock, depending upon market conditions, the 
Company's financial condition, anticipated capital requirements and 
liquidity, among other factors.

6.  SALE OF OIL AND GAS PROPERTIES

    The Company sold certain of its oil and gas properties and related assets 
on January 21, 1999, for approximately $26,000,000 (subject to certain 
closing and post closing adjustments).  The assets sold consisted of all of 
the Company's interest in 16,253 gross acres and 135 producing wells and 
related equipment in the Bonny Field in Yuma County, Colorado.  Prima also 
sold its 15.5% interest in the Bonny Gathering Company joint venture, which 
owned the pipeline, gathering, compression and dehydration facilities at the 
Bonny Field.  Prima had served as the managing venturer and operator of Bonny 
Gathering Company since initial development of the field in 1982.
  
    The sales proceeds have been placed in a like-kind exchange escrow 
account with Norwest Bank Colorado, National Association as escrow agent.  
The Company intends to identify and close on certain qualifying properties 
pursuant to the like-kind exchange provisions of Section 1031 of the Internal 
Revenue Code of 1986.  Pursuant to these tax provisions, Prima must identify 
the qualifying properties within 45 days and close within 180 days of the 
closing of the Bonny Field transaction. On March 5, 1999, the Company filed a 
listing of qualifying properties with the escrow agent.  This list included 
oil and gas properties and other real estate properties.  There is no 
assurance the Company will be able to close on these properties within the 
applicable time limit.  To the extent the Company does not close on 
qualifying properties, the unexpended funds will be disbursed from the escrow 
account to Prima and will be subject to federal and state income taxes of 
approximately $6 million after utilization of minimum tax credit 
carryforwards..

    The Company has reflected the proceeds received attributable to the 
producing wells and leasehold interests as a credit to the carrying value of 
its oil and gas properties, as the properties sold were less than 25% of the 
Company's proved reserves.

                                       10
<PAGE>

                            PRIMA ENERGY CORPORATION
                MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
                      CONDITION AND RESULTS OF OPERATIONS

LIQUIDITY AND CAPITAL RESOURCES

    The Company's principal internal sources of liquidity are cash flows 
generated from operations and existing cash and cash equivalents.  Net cash 
provided by operating activities for the three months ended March 31, 1999 
was $3,536,000 compared to $7,024,000 for the same three month period of 
1998.  Net working capital at March 31, 1999 was $3,562,000 (net of 
$25,951,000 held in a like-kind exchange escrow account) compared to 
$5,467,000 at December 31, 1998.  Current liabilities at March 31, 1999 
decreased from December 31, 1998 amounts by $1,083,000, while current assets 
decreased by $2,988,000 (net of the funds held in a like-kind exchange escrow 
account) for the same period.  Cash flow from operations in the first quarter 
of 1998 benefited from a contract settlement payment of $3,850,000, due to 
the early termination of a gas supply contract.

    The Company has external borrowing capacity of $8,000,000 through an 
unsecured line of credit with a commercial bank, all of which is available to 
be drawn.  On January 21, 1999, Prima closed on the sale of all of its 
interest in the Bonny Field acreage, wells, and gathering system for 
approximately $26 million.  Prima placed the proceeds from this sale in a 
like-kind exchange escrow account with a qualified intermediary with the 
intent of identifying and closing on certain qualifying properties pursuant 
to like-kind exchange provisions of Section 1031 of the Internal Revenue 
Code. These qualifying properties include oil and gas properties and other 
real estate properties.  In the event the Company is unable to close on 
qualifying properties pursuant to these requirements, the proceeds will be 
taxable.

    The Company invested $4,124,000 in property and equipment during the 
quarter ended March 31, 1999, compared to $2,877,000 for the 1998 quarter.  
The Company expended $2,605,000 during the 1999 quarter for its proportionate 
share of the costs of drilling, completing and refracturing wells, $689,000 
for undeveloped acreage, $67,000 for developed properties and $763,000 for 
other property and equipment.  These expenditures compare to $2,315,000 for 
well costs, $384,000 for undeveloped acreage and $178,000 for other equipment 
in the 1998 quarter. The Company also expended $1,240,000 for the purchase of 
treasury stock during the first quarter of 1999.

    During the first quarter of 1999, the Company participated in the 
refracturing of nineteen gross (16.2 net) wells in the Wattenberg Area of the 
Denver Basin.  All of these wells have been successfully completed and placed 
back on production.  Production increases have averaged 180 Mcf of natural 
gas and 8 barrels of oil per day.  Current plans are to refrac or recomplete 
an additional 37 wells in this area during the remainder of 1999, and to 
drill approximately 9 new wells in the Wattenberg Area and on leases at 
Denver International Airport, at an estimated combined gross capital 
expenditure of $6.2 million.  To date in the second quarter, five additional 
refrac wells have been completed and placed on production.

                                       11
<PAGE>

    The Company drilled and set pipe on an offset well in the Cedar Draw area 
of the Powder River Basin of Wyoming during the first quarter of 1999.  This 
well, the Cedar Draw Federal 11-21, in which Prima owns a 100% working 
interest, is currently scheduled to be completed in June of 1999.  The 
Company anticipates drilling three additional 10,000 foot Muddy Formation 
test wells in this area during the remainder of 1999, at an estimated capital 
expenditure of $2.5 million.

    The Company continues to participate in the development of the Cave Gulch 
area in the Wind River Basin of Wyoming.  Prima participated in the drilling 
of three non-operated wells during the first quarter of 1999 and in the 
completion of a well which was drilled in December 1998. Prima's working 
interests in these wells range from 6% to 15%.  Three of the four wells were 
producing as of May 10, 1999 and one was drilling.

    During the first quarter of 1999, the Company acquired additional 
undeveloped acreage, primarily by adding to its acreage position in the 
Powder River Basin, where the Company owns about 100,000 acres in the 
burgeoning coalbed methane play.

    During March of 1999, the Company formed a new subsidiary oilfield 
service company, Action Energy Services ("AES").  AES is a Wyoming 
corporation formed to provide services for Prima and other parties in the 
Powder River Basin area.  AES acquired the assets of Star Drilling Company 
for $460,000 and other service equipment for $283,000 during the first 
quarter of 1999. AES anticipates generating its first revenues during the 
second quarter of this year.

    The Company regularly reviews opportunities for acquisition of assets or 
companies related to the oil and gas industry which could expand or enhance 
its existing business.  The Company expects its operations, including 
acquisition, drilling, completion and recompletion well costs, will be 
financed by funds provided by operations, working capital, borrowings on the 
line of credit, various cost-sharing arrangements, or from other financing 
alternatives. 

YEAR 2000 ISSUE

    The Year 2000 Issue is the result of computer applications being written 
using two digits rather than four to define the applicable year.  As the year 
2000 approaches, such applications may be unable to accurately process 
certain date-based information.  The Company believes it has identified the 
significant internal computer applications that will require modification to 
ensure Year 2000 compliance.  Internal and external resources are being used 
to make the required modifications and test compliance.  Modification and 
compliance is proceeding as scheduled and the Company expects that the 
modifications should be completed by June 30, 1999.  At that time, the 
Company's internal computer applications are expected to be Year 2000 
compliant.

    An assessment of the readiness of third parties with whom the Company 
does business, such as customers and vendors, is ongoing.  Third parties with 
whom the Company has material relationships have been contacted regarding 
their Year 2000 issues and responses are being monitored to determine the 
potential effect on Prima.  The Company's operations would be impacted by 
various third parties abilities to be Year 2000 compliant.

    The failure to correct a material Year 2000 problem could result in an 
interruption in, or failure of, certain normal business activities or 
operations.  Such failures could materially and adversely affect the 
Company's results of operations, liquidity and financial condition.  The 
Company 

                                       12
<PAGE>

has not yet determined the potential adverse effect that Year 2000 risks may 
have on its financial condition, liquidity or results of operations. The 
Company's program is expected to significantly reduce the Company's level of 
uncertainty about Year 2000 issues and, in particular, about Year 2000 
compliance and readiness of its third party vendors and associates.  The 
Company believes that, with the modification of its business systems and 
completion of its assessment program as scheduled, the possibility of 
significant interruptions of normal operations should be reduced.  The cost 
of Year 2000 compliance has not been specifically tracked but is not 
anticipated to be material to the Company's financial position or results of 
operations in any given year.

    To mitigate Year 2000 compliance issues at year end, the Company will 
back up all internal computer data to ensure the ability to restore that 
information.  The Company will have hard copies of all important internal 
computer information and hard copies of the detail of any assets held by 
third parties such as banks and investment brokers.   If the Company is 
unable to produce its wells or transport or sell its production due to Year 
2000 compliance issues, wells will be shut-in until normal operations can be 
resumed.

RESULTS OF OPERATIONS
    
    For the quarter ended March 31, 1999, the Company earned net income of 
$1,515,000, or $.26 per diluted share, on revenues of $5,789,000, compared to 
net income of $4,139,000, or $.70 per diluted share on revenues of 
$11,178,000 for the comparable quarter of 1998.  Expenses were $3,699,000 for 
the 1999 quarter compared to $5,149,000 for the 1998 quarter.  Revenues 
decreased $5,389,000, or 48%, expenses decreased $1,450,000, or 28% and net 
income decreased $2,624,000, or 63%.  During the first quarter of 1998, the 
Company recorded non-recurring revenues of $3,850,000 ($2,500,000 after 
taxes) from the early termination of a gas sales agreement. 

    Oil and gas sales for the quarter ended March 31, 1999 were $3,826,000 
compared to $4,150,000 for the same period of 1998, a decrease of $324,000 or 
8%.  The decrease is attributable to significantly lower oil and gas prices, 
which were partially offset by increased production for both oil and natural 
gas.  The Company's net natural gas production was 1,748,000 Mcf and 
1,510,000 Mcf for the first quarters of 1999 and 1998, respectively, an 
increase of 238,000 Mcf or 16%.  The Company's net oil production was 81,000 
barrels compared to 68,000 barrels for the same periods, an increase of 
13,000 barrels or 19%.  Net production on a BOE basis increased 17% from 
319,000 BOE to 372,000 BOE.

    The average price received for natural gas production was $1.66 per Mcf 
for the 1999 quarter compared to $2.10 per Mcf for the 1998 quarter, a 
decrease of $0.44 per Mcf or 21%. Approximately 5% of the natural gas 
production at March 31, 1998 was attributable to production sold under a 
fixed contract price of $5.90 per MMBtu.  The average price for the Company's 
natural gas production exclusive of the fixed price contract gas was $1.91 
for the 1998 quarter.  The wells subject to the fixed price contract were 
sold by the Company effective January 1, 1999.  The average price received 
for oil in 1999 was $11.42 per barrel compared to $14.49 per barrel for the 
same period of 1998, a decrease of $3.07 per barrel or 21%.  During the first 
quarter of 1999, the Company hedged approximately 21% of its natural gas 
production.  Hedging gains of $55,000 are included in oil and gas revenues 
for this period, which increased the average price received per Mcf of 
natural gas by $0.03.  No oil production was hedged during the first quarter 
of 1999.   During the first quarter of 1998, the Company hedged approximately 
51% of its natural gas production. 

                                       13
<PAGE>

Hedging losses of $126,000 are included in oil and gas revenues for this 
period, which decreased the average price received per Mcf of natural gas by 
$0.08.  No oil production was hedged during the first quarter of 1998. 

    Lease operating expenses and production taxes ("LOE") were $795,000 for 
the 1999 quarter compared to $849,000 for the 1998 quarter, a decrease of 
$54,000 or 6%.  Depreciation, depletion and amortization ("DD&A") was 
$1,309,000 for the first quarter of 1999 compared to $1,505,000 for the first 
quarter of 1998, a decrease of $196,000 or 13%.  Production for the quarter 
ended March 31, 1999 was 372,000 BOE compared to 319,000 BOE for the quarter 
ended March 31, 1998.  LOE per equivalent barrel of production was $2.13 for 
the first quarter of 1999 compared to $2.66 for the comparable quarter of 
1998.  The rates for 1998 were higher than those experienced in 1999 due to 
workover expenses and additional production taxes resulting from higher 
product prices.  DD&A applicable to oil and gas properties was $3.07 per 
equivalent barrel of production for the 1999 quarter compared to $4.30 per 
equivalent barrel of production for the 1998 quarter.  The DD&A rate is lower 
in 1999 due to the lower net carrying value of oil and gas properties 
resulting from the crediting of proceeds from the sale of the Bonny wells to 
the full cost pool.  Depreciation of other property and equipment was 
$167,000 and $131,000 for the quarters ended March 31, 1999 and 1998, 
respectively.

    Trading revenues and cost of trading represent the marketing of third 
party natural gas by Prima Natural Gas Marketing, Inc., a wholly owned 
subsidiary.  Trading revenues were $417,000 for the three months ended March 
31, 1999, a $1,232,000, or 75% decrease from the $1,649,000 reported for the 
three months ended March 31, 1998.  The Company marketed 180,000 MMBtus for 
the first quarter of 1999 compared to 598,000 MMBtus marketed during the 
comparable quarter of 1998, a decrease of 418,000 or 70%.  Costs of trading 
were $354,000 for the 1999 quarter compared to $1,410,000 for the 1998 
quarter, a decrease of $1,056,000 or 75%.  Trading activities fluctuate with 
natural gas markets and the Company's ability to develop markets that meet 
the Company's trading criteria.

    Oilfield services represent the revenues earned by Action Oilfield 
Services, Inc., a wholly owned subsidiary.  These revenues include well 
servicing fees from completion and swab rigs, trucking, water hauling and 
rental equipment, and other related activities.  Revenues from third parties 
were $1,032,000 for the quarter ended March 31, 1999 compared to $1,128,000 
for the comparable quarter of 1998.  This $96,000, or 9%, decrease in 
revenues was attributable to a higher percentage of work being performed on 
Prima wells, which is eliminated in the consolidated financial statements.  
For the quarter ended March 31, 1999, 26% of the fees billed by Action were 
for Company owned wells compared to 9% for the quarter ended March 31, 1998.  
Costs of oilfield services were $667,000 for the quarter ended March 31, 1999 
compared to $864,000 for the same quarter of 1998, a decrease of $197,000 or 
23% which is largely attributable to the elimination of costs associated with 
the Company's wells in the consolidated financial statements.

    Management and operator fees are earned pursuant to the Company's roles 
as operator for oil and natural gas wells (approximately 375 at March 31, 
1999 and 1998), located primarily in the Wattenberg Field area of Weld 
County, Colorado, and as managing venturer of a joint venture which owned gas 
gathering and pipeline facilities in the Bonny Field in Yuma County, 
Colorado.  The Company is a working interest owner in each of the operated 
wells.  The Company is paid operating and management fees by the other 
working interest owners in the properties.  Fees fluctuate with the number of 
wells operated, the percentage working interest in a property owned by third 
parties, 

                                       14
<PAGE>

and the amount of drilling activity during the period.  Fees for the first 
quarter of 1999 were $240,000 compared to $252,000 for the same period of 
1998, a decrease of $12,000 or 5%.  In January 1999, the Company sold its 
interest in the Bonny Field assets, but continued to provide various services 
to the new owner through March 31, 1999.  Management and operator fees 
attributable to the Bonny Field system were $66,000 and $101,000 for 1999 and 
1998, respectively.

    General and administrative expenses were $574,000 for the quarter ended 
March 31, 1999 compared to $521,000 for the quarter ended March 31, 1998, an 
increase of $53,000 or 10%.  The Company's general and administrative costs 
have increased due to expansion of the Company's areas of activity.

    The provision for income taxes decreased $1,315,000 to $575,000 for the 
three months ended March 31, 1999 compared to $1,890,000 for the three months 
ended March 31, 1998. The decrease was attributable to the decrease in income 
before income taxes, which totaled $2,090,000 for the 1999 quarter compared 
to $6,029,000 for the 1998 quarter, a decrease of $3,939,000, or 65%.  The 
effective income tax rate decreased from 31.4% for the 1998 quarter to 27.5% 
for the 1999 quarter.  Effective tax rates are affected by amounts of 
permanent differences between financial and taxable income, consisting 
primarily of statutory depletion deductions and Section 29 tax credits.

    Historically, oil and natural gas prices have been volatile and are 
likely to continue to be volatile.  Prices are affected by, among other 
things, market supply and demand factors, market uncertainty, and actions of 
the United States and foreign governments and international cartels. These 
factors are beyond the control of the Company.  To the extent that oil and 
gas prices decline, the Company's revenues, cash flows, earnings and 
operations would be adversely impacted.  The Company is unable to accurately 
predict future oil and natural gas prices.

    The Company's primary source of revenues is from the sale of oil and 
natural gas production.  Levels of revenues and earnings are affected by 
volumes of oil and natural gas production and by the prices at which oil and 
natural gas are sold.  As a result, the Company's operating results for any 
period are not necessarily indicative of future operating results because of 
fluctuations in oil and natural gas prices and production volumes.

       QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

    The Company's primary market risks relate to changes in the prices 
received from sales of oil and natural gas.  The Company's primary risk 
management strategy is to partially mitigate the risk of adverse changes in 
its cash flows caused by deceases in oil and natural gas prices by entering 
into derivative commodity instruments, including commodity futures contracts 
and price swaps.  By hedging only a portion of its market risk exposures, the 
Company is able to participate in the increased earnings and cash flows 
associated with increases in oil and natural gas prices; however, it is 
exposed to risk on the unhedged portion of its oil and natural gas 
production. 

    Historically, the Company has attempted to hedge the exposure related to 
its forecasted oil and natural gas production in amounts which it believes 
are prudent based on the prices of available derivatives and, in the case of 
production hedges, the Company's deliverable volumes.  The Company does not 
use or hold derivative instruments for trading purposes nor does it use 
derivative instruments with leveraged features.  The Company's derivative 
instruments are designed and 

                                       15
<PAGE>

effective as hedges against its identified risks, and do not of themselves 
expose the Company to market risk because any adverse change in the cash 
flows associated with the derivative instrument is accompanied by an 
offsetting change in the cash flows of the hedged transaction.

    Note 4 to the unaudited consolidated  financial statements provides 
further disclosure with respect to derivatives and related accounting 
policies.

    All derivative activity is carried out by personnel who have appropriate 
skills, experience and supervision.  The personnel involved in derivative 
activity must follow prescribed trading limits and parameters that are 
regularly reviewed by the Company's Chief Executive Officer.  All hedges or 
open positions are reviewed by the Chief Executive Officer before they are 
committed to, and significant positions are reviewed by the Company's Board 
of Directors.  The Company uses only well-known, conventional derivative 
instruments and attempts to manage its credit risk by entering into financial 
contracts with reputable financial institutions.

    Following are disclosures regarding the Company's market risk 
instruments.  Investors and other users are cautioned to avoid simplistic use 
of these disclosures.  Users should realize that the actual impact of future 
commodity price movements will likely differ from the amounts disclosed below 
due to ongoing changes in risk exposure levels and concurrent adjustments to 
hedging positions.  It is not possible to accurately predict future movements 
in oil and natural gas prices.

    The Company periodically hedges a portion of the price risk associated 
with the sale of its oil and natural gas production through the use of 
derivative commodity instruments, which consist of commodity futures 
contracts and price swaps.  These instruments reduce the Company's exposure 
to decreases in oil and natural gas prices on the hedged portion of its 
production by enabling it to effectively receive a fixed price on its oil and 
natural gas sales.  As of May 12, 1999, the Company had the following 
derivative positions in place:

<TABLE>
<CAPTION>
                                      Volume                                 Unrealized
Type of Derivative                (Bbls) or (Mcf)           Term             Gain/(Loss)  
------------------------------    ---------------     -----------------      -----------
<S>                               <C>                 <C>                    <C>
Oil futures                           16,000          June 1999               $(13,620)
Oil futures                            5,000          July 1999                  2,700
Oil calls                             10,000          July 1999                 (3,050)
Natural gas calls                    100,000          June 1999                 (9,400)
Natural gas calls                    100,000          July 1999                 (5,800)
Natural gas calls                    100,000          August 1999               (9,700)
Natural gas commodity swap           300,000          May-October 1999         (48,000)
Natural gas commodity swap           250,000          June-October 1999        (27,500)
</TABLE>

    During the first quarter of 1999, the Company sold 81,000 barrels of oil. 
 A hypothetical decrease of $1.14 per barrel (10% of average first quarter 
prices) would have decreased the Company's production revenues by $92,000 for 
that period.  The Company sold 1,748,000 Mcf of natural gas during the first 
quarter of 1999.  A hypothetical decrease of $.166 per Mcf (10% of average 
first quarter prices) would have decreased the Company's production revenues 
by $290,000 for that period.
                                       16
<PAGE>

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

             CAUTIONARY STATEMENT FOR PURPOSES OF THE "SAFE HARBOR"
       PROVISIONS OF THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995

    "Management's Discussion and Analysis of Financial Condition and Results 
of Operations" included in Item 2 of this Report contains "forward-looking 
statements" and are made pursuant to the "safe harbor" provisions of the 
Private Securities Litigation Reform Act of 1995.  These statements include, 
without limitation, statements relating to liquidity, financing of 
operations, capital expenditures budget (both the amount and the source of 
funds), continued volatility of oil and natural gas prices, future drilling 
plans and other such matters.  The words "anticipates," "expects" or 
"estimates" and similar expressions identify forward-looking statements.  
Such statements are based on certain assumptions and analyses made by the 
Company in light of its experience and its perception of historical trends, 
current conditions, expected future developments and other factors it 
believes are appropriate in the circumstances.  Prima does not undertake to 
update, revise or correct any of the forward-looking information.  Factors 
that could cause actual results to differ materially from the Company's 
expectations expressed in the forward-looking statements include, but are not 
limited to, the following:  industry conditions; volatility of oil and 
natural gas prices; hedging activities; operational risks (such as blowouts, 
fires and loss of production); insurance coverage limitations; potential 
liability imposed by government regulation (including environmental 
regulation); the need to develop and replace its oil and natural gas 
reserves; the substantial capital expenditures required to recover its 
operations; risks related to exploration and developmental drilling; and 
uncertainties about oil and natural gas reserve estimates.  For a more 
complete explication of these various factors, see "Cautionary Statement for 
the Purposes of the 'Safe Harbor' Provisions of the Private Securities 
Litigation Reform Act of 1995" included in the Company's Annual Report on 
Form 10-K for the year ended December 31, 1998, beginning on page 16.

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

PART II  OTHER INFORMATION

ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K

         (A)   EXHIBITS

         The following exhibit is filed herewith pursuant to Rule 601 of 
Regulation S-K.

<TABLE>
<CAPTION>
    EXHIBIT NO.                              DOCUMENT
<S>                                          <C>
    27                                       Financial Data Schedules
</TABLE>

         (B)   REPORTS ON FORM 8-K

         A Form 8-K dated January 21, 1999, announced the sale of oil and gas 
properties and related assets for $26 million.  See Note 6 of the Notes to 
Unaudited Consolidated Financial Statements for additional discussion of this 
transaction.

                                       17
<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.

                                               PRIMA ENERGY CORPORATION
                                                     (Registrant)



Date          May 14, 1999                     By /s/ Richard H. Lewis
     ---------------------------                 -------------------------------
                                      
                                               Richard H. Lewis,
                                               President and
                                               Principal Financial Officer














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