EXHIBIT 10.20




                             AMENDMENT
               to Renewal Promissory Note dated May 1, 1998
            in the original principal amount of $3,370,694.12
               executed by FUTURE PETROLEUM CORPORATION,
                      a Utah corporation,
                 and payable to the order of
                ENERGY CAPITAL INVESTMENT COMPANY PLC

THIS AMENDMENT is attached to, made a part of, and amends 
that certain Renewal Promissory Note dated May 1, 1998 (the 
"Note") in the original principal amount of $3,370,694.12, 
executed by Future Petroleum Corporation, a Utah Corporation 
("Future") and payable to the order of Energy Capital Investment 
Company PLC, an English investment company ("Lender").

The Note was issued in connection with and pursuant to (i) 
that certain Purchase and Sale Agreement dated November 25, 1997 
between Future and Energy Capital Investment Company PLC, EnCap 
Equity 1994 Limited Partnership and Gecko Booty 1994 I Limited 
Partnership and (ii) that certain Purchase and Sale Agreement 
dated May 1, 1998 between Future and Energy Capital Investment 
Company PLC, EnCap Equity 1994 Limited Partnership and NCI 
Enterprises, Inc., each of which has been restated and superseded 
by that certain Note Restructuring Agreement of even date 
herewith among Future, Energy Capital Investment Company PLC and 
EnCap Equity 1994 Limited Partnership, as from time to time 
amended, supplemented or restated (the "Note Agreement").

Future and Lender hereby agree to amend the terms of the 
Note to provide that, notwithstanding the payment schedule 
specified in the Note, interest on, and the principal amount of, 
the Note, shall be due and payable as follows:

Interest only on the Note shall be due and payable quarterly 
as it accrues on the last business day of each quarter, 
beginning September 30, 1998 and continuing regularly 
thereafter until and including December 31, 2003, on which 
date all unpaid principal of and accrued interest on the 
Note shall be due and payable.

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Future and Lender hereby further agree that, notwithstanding 
anything in the Note or in the Note Agreement to the contrary, 
Future shall have the option, exercisable with respect to each of 
the first eight quarterly installments of interest due under the 
Note, not to pay any such quarterly installment of interest, in 
which event (a) such non-payment of interest shall not constitute 
a "Default" or "Event of Default," as such terms are defined in 
the Note Agreement, (ii) any such unpaid installment of interest 
shall not bear interest at the default rate set forth in the 
second paragraph of the Note and (iii) the amount of any unpaid 
installment of interest shall automatically be added to the 
principal amount of the Note, effective as of the date such 
unpaid installment of interest was due under the Note, and shall 
bear interest at the rate of interest set forth in the Note.

IN WITNESS WHEREOF, Future has caused this Amendment to be 
executed and delivered by an officer thereunto validly 
authorized, and Lender has accepted this Amendment and caused the 
same to be attached to and become a part of the Note.

Date: August 14, 1998
FUTURE PETROLEUM CORPORATION,
a Utah corporation


By:/s/ B. Carl Price     
B. Carl Price, President

Accepted this 14th day of August, 1998

ENERGY CAPITAL INVESTMENT COMPANY PLC


By: /s/ Gary R. Petersen                                  
Gary R. Petersen, Director
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