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

                                    FORM 8-K

                                 CURRENT REPORT

     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

      Date of Report (Date of earliest event reported): September 30, 2005

                        PIONEER NATURAL RESOURCES COMPANY
             (Exact name of registrant as specified in its charter)


           Delaware                   1-13245               75-2702753
       (State or other              (Commission          (I.R.S. Employer
jurisdiction of incorporation)      File Number)      Identification Number)

    5205 N. O'Connor Blvd                                     75039
          Suite 900                                         (Zip code)
        Irving, Texas
   (Address of principal
     executive offices)


       Registrant's telephone number, including area code: (972) 444-9001

                                 Not applicable
          (Former name or former address, if changed since last report)


Check  the  appropriate  box  below  if the  Form  8-K  filing  is  intended  to
simultaneously  satisfy the filing obligation of the registrant under any of the
following provisions:


[ ] Written communications pursuant to Rule 425 under the Securities Act (17 CFR
230.425)


[ ] Soliciting material  pursuant to Rule 14a-12  under the Exchange Act (17 CFR
240.14a-12)


[ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange
Act (17 CFR 240.14d-2(b))


[ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange
Act (17 CFR 240.13e-4(c))






                        PIONEER NATURAL RESOURCES COMPANY


                                TABLE OF CONTENTS

                                                                       Page

Item 1.01.     Entry into a Material Definitive Agreement...............3

Item 2.02.     Results of Operations and Financial Conditions...........4

Item 2.03.     Creation of a Direct Financial Obligation or an
               Obligation Under an Off-Balance Sheet Arrangement
               of a Registrant..........................................4

Item 9.01.     Financial Statements and Exhibits........................4

               (c)   Exhibits...........................................4

Signature...............................................................5

Exhibit Index...........................................................6



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                       PIONEER NATURAL RESOURCES COMPANY


Item 1.01.   Entry into a Material Definitive Agreement

     On September 30, 2005,  Pioneer Natural  Resources Company (the "Company"),
as  Borrower,   JPMorgan  Chase  Bank,  N.A.  as  Administrative  Agent,  and  a
syndication of participating  banks (collectively with JPMorgan Chase Bank, N.A,
the  "Lenders")  entered into an Amended and Restated  5-Year  Revolving  Credit
Agreement  (the  "Amended  Credit  Agreement")  that  amended and  restated  the
Company's  5-Year  Revolving Credit Agreement dated as of December 16, 2003. The
Amended  Credit  Agreement  matures  in  September  2010,  or such later date as
maturity with respect to the loan  commitments  of  consenting  Lenders shall be
extended (not to exceed three one-year  extensions) in accordance with the terms
of the  Amended  Credit  Agreement.  The terms of the Amended  Credit  Agreement
provide for initial  aggregate loan  commitments  of $1.5 billion,  which may be
increased to a maximum  aggregate amount of $1.8 billion if the Lenders increase
their loan commitments or if loan commitments of new financial  institutions are
added to the Amended  Credit  Agreement.  Borrowings  under the  Amended  Credit
Agreement may be in the form of revolving  loans or swing line loans.  Aggregate
outstanding  swing line loans may not exceed $100 million.  Revolving loans bear
interest,  at the option of the Company,  based on (a) a rate per annum equal to
the higher of the prime rate  announced from time to time by JPMorgan Chase Bank
or the weighted  average of the rates on overnight  Federal  funds  transactions
with members of the Federal  Reserve System during the last  preceding  business
day plus 0.5 percent or (b) a base Eurodollar rate,  substantially  equal to the
London Interbank Offered Rate ("LIBOR"), plus a margin (the "Applicable Margin")
that is  determined  by reference to a grid based on the  Company's  debt rating
(currently  .625  percent).  Swing line loans bear  interest at a rate per annum
equal to the "ASK" rate for  Federal  funds  periodically  published  by the Dow
Jones Market Service plus the  Applicable  Margin.  The Company pays  commitment
fees on the  undrawn  amounts  under  the  Amended  Credit  Agreement  that  are
determined  by reference  to a grid based on the  Company's  debt rating,  which
commitment  fees were 0.125  percent  per annum at  September  30,  2005.  As of
September 30, 2005,  the Company had $755.0  million  borrowed under the Amended
Credit  Agreement,  bearing  interest at an  effective  rate of 4.75 percent per
annum.

     Many of the parties to the Amended Credit Agreement are also counterparties
to the Company's  derivative  instruments and provide other banking,  investment
banking and  brokerage  services to the Company in the ordinary  course of their
businesses.

     The Amended Credit Agreement  contains certain financial  covenants,  which
include the maintenance of a ratio of the Company's earnings before gain or loss
on the  disposition of assets,  interest  expense,  income taxes,  depreciation,
depletion and amortization  expense,  exploration and  abandonments  expense and
other noncash charges and expenses to consolidated  interest expense of at least
3.5 to 1.0;  maintenance  of a ratio of total debt to book  capitalization  less
intangible assets (other than intangible oil and gas assets),  accumulated other
comprehensive income and certain noncash asset write-downs not to exceed 0.60 to
1.0;  and if the Company  should fall below an  investment  grade rating by both
Moody's  Investors Service and Standard and Poor's prior to the date, if any, on
which  its  investment  grade  rating  by  either  of such  rating  agencies  is
determined  to be  stable  under  the  terms of the  Amended  Credit  Agreement,
maintenance of an annual ratio of the net present value of the Company's oil and
gas  properties  to total  debt of at least  1.50 to 1.0 for the first 18 months
following the date of the Amended Credit Agreement,  and 1.75 to 1.0 thereafter.
The terms of the Amended Credit Agreement provide for customary  representations
and warranties, negative and affirmative covenants (in addition to the financial
covenants  described  above) and events of default.  The lenders may declare any
outstanding  obligations under the Amended Credit Agreement  immediately due and
payable upon the occurrence, and during the continuance of, an event of default,
which includes a defined change in control of the Company.

     As of September 30, 2005, the Company had $35.3 million of undrawn  letters
of credit under the Amended Credit Agreement, subject to a per annum fee of 0.75
percent.  As of September 30, 2005, the Company had unused borrowing capacity of
$709.7 million under the Amended Credit Agreement.

     The Company was a borrower under its 364-Day Credit  Agreement  dated as of
September  28, 2004,  which  agreement  was scheduled to mature on September 27,
2005.  To  accommodate  the  timing  of  the  execution  of the  Amended  Credit
Agreement, the Company and its lenders converted the outstanding loans under the
364-Day  Credit  Agreement to term loans and extended the maturity of such loans
by up to fifteen  business  days. In connection  with the funding of the Amended
Credit  Agreement  on  September  30, 2005,  all amounts  outstanding  under the
364-Day  Credit   Agreement  were  retired  and  the  364-Day  Credit  Agreement
terminated.


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                       PIONEER NATURAL RESOURCES COMPANY


     The Amended Credit Agreement is attached as exhibit 99.1, and the terms and
conditions thereof are incorporated herein by reference.

Item 2.02.   Results of Operations and Financial Condition

     On September 30, 2005,  the Company  issued a news release that is attached
hereto as exhibit 99.2. In the news release,  the Company  announced that it has
accepted tenders to repurchase  $188.4 million of its outstanding  5.875% Senior
Notes due 2012 (the "5.875% Notes").

     On October 3, 2005,  the  Company  issued a news  release  that is attached
hereto as exhibit 99.3. In the news release,  the Company  announced that it has
redeemed for cash all of its outstanding  9-5/8% Senior Notes due 2010 and 7.50%
Senior Notes due 2012 (the  "Notes").  In total,  Pioneer paid $34.6  million in
connection with the redemption of the Notes.

     Associated  with the  redemption of the Notes and the completed debt tender
offer for the 5.875%  Notes,  the  Company  will  recognize  a pretax  charge of
approximately $14 million in its reported third quarter of 2005 results.

Item 2.03.   Creation of a Direct Financial Obligation or an Obligation under an
             Off-Balance Sheet Arrangement of a Registrant

     The  information  described  above  under  "Item 1.01 Entry into a Material
Definitive Agreement" is incorporated herein by reference.

Item 9.01.   Financial Statements and Exhibits

        (c)    Exhibits

               99.1 - Amended and Restated  5-Year  Revolving  Credit  Agreement
                      dated  as of  September 30,  2005  among  the Company,  as
                      Borrower,  JPMorgan  Chase  Bank,  N.A. as  Administrative
                      Agent and certain other lenders.
               99.2 - News Release dated September 30, 2005.
               99.3 - News Release dated October 3, 2005.


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                       PIONEER NATURAL RESOURCES COMPANY


                                    SIGNATURE

     Pursuant to the  requirements  of the Securities  Exchange Act of 1934, the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned hereunto duly authorized.

                                   PIONEER NATURAL RESOURCES COMPANY

                                       /s/ Darin G. Holderness
                                   ---------------------------------------------
                                   Darin G. Holderness
                                   Vice President and Chief Accounting Officer

Date:  October 4, 2005


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                       PIONEER NATURAL RESOURCES COMPANY


                                  EXHIBIT INDEX

Exhibit
Number          Exhibit Title
-------         -------------

 99.1(a)        Amended and Restated  5-Year  Revolving  Credit  Agreement dated
                as of  September  30,  2005  among  the  Company,  as  Borrower,
                JPMorgan Chase Bank,  N.A. as  Administrative  Agent and certain
                other lenders.

 99.2(a)        News Release dated September 30, 2005.

 99.3(a)        News Release dated October 3, 2005.

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

(a) Filed herewith.



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