April 13, 2006


Via EDGAR submission and U.S. mail
- ----------------------------------

Securities and Exchange Commission
Division of Corporate Finance
100 F Street, N.E., Mail Stop 7010
Washington, D.C. 20549-7010

Attention: April Sifford

       Re: Pioneer Natural Resources Company
           Form 10-K, Filed February 17, 2006
           File No. 001-13245

Dear Ms. Sifford:

     We are writing to respond to the  comments  of the Staff of the  Securities
and  Exchange  Commission  with  respect to our Form 10-K in the comment  letter
dated  March 31, 2006 (the  "Comment  Letter"),  addressed  to Richard P. Dealy,
Executive  Vice  President  and  Chief  Financial  Officer  of  Pioneer  Natural
Resources Company ("Pioneer" or the "Company").

Comment Responses
- -----------------

     The bold  typeface,  numbered  paragraphs and headings below are taken from
the Comment Letter. Our response to each such comment follows in plain text.

              Form 10-K for the Fiscal Year Ended December 31, 2005

Management's Discussion and Analysis..., page 36
- ------------------------------------------------

Hedging Activities, page 41
- ---------------------------

1.   We note that your  commodity  price hedges  decreased  oil and gas revenues
     from  continuing  operations by $420.4  million,  $211.9 million and $110.7
     million,  in  2005,  2004  and  2003,  respectively.   Please  expand  your
     discussion  and  analysis  to more  clearly  explain  your  objectives  and
     strategies to manage market risk exposures. Explain whether you believe any
     change in your  strategies  is  warranted,  given your trend of losses from
     risk management activities.

     Response: Within Item 7. "Management's Discussion and Analysis of Financial
     Condition and Results of  Operations"  and Note J of Notes to  Consolidated
     Financial  Statements  included  in  Item  8.  "Financial   Statements  and
     Supplementary  Data" of Pioneer's 2005 Form 10-K, the Company  discloses to
     readers that it utilizes  commodity  swap and collar  contracts in order to
     (i) reduce the effect of price  volatility on the  commodities  the Company
     produces and sells, (ii) support the Company's annual capital budgeting and
     expenditure  plans and (iii) reduce  commodity  price risk  associated with
     certain capital budgets. Additionally, the Company discloses in (a) Item 1.
     "Business  - Business  Activities  - Petroleum  Industry"  that oil and gas






April Sifford
Securities and Exchange Commission
Page 2
April 13, 2006


     prices have  increased  during recent years and that it utilizes  commodity
     hedges  to  mitigate  the  impact  of  commodity  price  volatility  on the
     Company's  net asset  value  and (b) Item 1A.  "Risk  Factors  -  Commodity
     Hedges"  that to the extent the Company  engages in hedging  activities  to
     reduce  commodity  price risk,  the Company may be prevented from realizing
     the benefits of price increases above the levels of the hedges. The Company
     respectfully  submits that its  disclosures of its commodity hedge strategy
     of  utilizing  swap and collar  contracts  to realize its  disclosed  hedge
     objectives are clearly described and meaningful to the readers.

          Although the  Company's  commodity hedging activities have resulted in
     hedge losses during  recent periods of rising  commodity prices,  Pioneer's
     execution of its hedging  strategy  has been  successful  in realizing  its
     stated objectives.  Central to those stated objectives is the mitigation of
     commodity  price  volatility  and risk.  The  Company  enters  into  highly
     effective   commodity   price  hedges  which,   when  entered   into,   are
     "at-the-market",   have  no  initial  intrinsic  value  and  have  as  much
     likelihood  of  resulting  in future hedge gains as they do of future hedge
     losses.  However,  whether they result in future hedge gains or losses they
     are  matched by equal  offsetting  losses or gains on the  hedged  physical
     commodity sales. Consequently, a disciplined hedge strategy is impartial to
     hedge gains or losses.

          Given that the Company's hedge objectives have not changed, changes in
     the Company's strategy of utilizing commodity  swap and collar contracts to
     realize those  objectives  are not  contemplated  at this time. The Company
     respectfully  submits that its disclosures of hedge objectives,  strategies
     and recent hedge  losses are not  conflicting  circumstances  nor warrant a
     change in strategy.

Consolidated Financial Statements, page 64
- ------------------------------------------

Unaudited Supplementary Information, page 116
- ---------------------------------------------

2.   We note that you present costs  incurred for asset  retirement  obligations
     separately from acquisition costs, exploration costs and development costs.
     Please remove the asset  retirement  obligations  column and reclassify the
     costs  accordingly as there is no provision for this column in paragraph 21
     and  Illustration 2 of SFAS 69. You may disclose the costs incurred related
     to asset retirement  obligations  through a footnote to the table. Refer to
     our         February         2004         industry         letter        at
     http://www.sec.gov/divisions/corpfin/guidance/oilgasletter.htm.

     Response:   Although  the  Company  believes  its  current  disclosure  was
     responsive to the February 2004 industry letter,  the Company  respectfully
     submits that in future filings it will change its supplementary  disclosure
     to reflect the asset retirement obligations in each category that gave rise
     to the  obligation  as  requested.  Also,  in order to further  enhance the
     disclosure,  the Company will supplementally footnote the incremental asset
     retirement  obligation  added  during the period.  Exhibit A to this letter
     provides an example of the Company's proposed tabular disclosure that would
     be provided in its 2006 Form 10-K.





April Sifford
Securities and Exchange Commission
Page 3
April 13, 2006


In connection with the Company's responses to the Staff's comments, Pioneer
acknowledges that:

   o  the Company is responsible for the adequacy and accuracy of the disclosure
      in the filing;
   o  Staff comments or  changes to  disclosure in response to Staff comments do
      not  foreclose the Commission from  taking any action with  respect to the
      filing; and
   o  the Company may not assert Staff comments  as a defense  in any proceeding
      initiated  by the  Commission or  any person  under the federal securities
      laws of the United States.

Please direct any  questions in connection  with the responses set forth in this
letter to Richard P. Dealy at 972-969-4054 (direct fax 972-969-3572).

                                               Very truly yours,


                                               /s/ Richard P. Dealy
                                               -----------------------------
                                               Richard P. Dealy
                                               Executive Vice President and
                                               Chief Financial Officer

Enclosures

Cc: Darin G. Holderness





                                    Exhibit A
                                    ---------


                        PIONEER NATURAL RESOURCES COMPANY

                       UNAUDITED SUPPLEMENTARY INFORMATION
                  Years Ended December 31, 2005, 2004 and 2003




Costs Incurred for Oil and Gas Producing Activities


                                        Property
                                    Acquisition Costs                                        Total
                                 -----------------------    Exploration    Development       Costs
                                   Proved      Unproved        Costs          Costs       Incurred (a)
                                 ----------    ---------    -----------    -----------    ------------
                                                                  (in thousands)
                                                                           
Year Ended December 31, 2005:
  United States...............   $  167,814    $ 60,561     $  217,723     $  457,292      $  903,390
  Argentina...................          -           512         36,878         92,250         129,640
  Canada .....................        2,593       7,344         43,437         77,863         131,237
  Africa and other............          -        30,923         63,605         20,741         115,269
                                  ---------     -------      ---------      ---------       ---------
    Total.....................   $  170,407    $ 99,340     $  361,643     $  648,146      $1,279,536
                                  =========     =======      =========      =========       =========

Year Ended December 31, 2004:
  United States...............   $2,213,879    $301,856     $  127,338     $  233,112      $2,876,185
  Argentina...................          -           -           49,745         52,707         102,452
  Canada .....................       46,988      20,921         33,406         19,311         120,626
  Africa and other............          -        18,238         32,932         23,736          74,906
                                  ---------     -------      ---------      ---------       ---------
    Total.....................   $2,260,867    $341,015     $  243,421     $  328,866      $3,174,169
                                  =========     =======      =========      =========       =========

Year Ended December 31, 2003:
  United States...............   $  130,876    $ 12,264     $  191,809     $  267,218      $  602,167
  Argentina...................           97       1,787         24,893         24,894          51,671
  Canada .....................           63       5,028         24,899         24,810          54,800
  Africa and other............          -           910         33,212         28,695          62,817
                                  ---------     -------      ---------      ---------       ---------
    Total ....................   $  131,036    $ 19,989     $  274,813     $  345,617      $  771,455
                                  =========     =======      =========      =========       =========
<FN>
- -------------
(a)  The Company  adopted SFAS 143 on January 1, 2003.  Total costs incurred for
     the years ended  December 31, 2005,  2004 and 2003 included  $19.2 million,
     $15.1  million  and  $48.5  million,   respectively,  of  asset  retirement
     obligations incurred related to new wells placed on production,  changes in
     estimates or  liabilities  assumed in  acquisitions.  See Notes B and L for
     additional   information   regarding   the   Company's   asset   retirement
     obligations.
</FN>