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As filed with the Securities and Exchange Commission on July 25, 2001
                                                      Registration No. 333-60470
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    ---------
                         POST-EFFECTIVE AMENDMENT NO. 1
                                       TO
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      Under
                           The Securities Act of 1933*

                                    ---------
                           PATTERSON-UTI ENERGY, INC.
             (Exact name of registrant as specified in its charter)

           Delaware                                      75-2504748
(State or other jurisdiction of             (I.R.S. Employer Identification No.)
incorporation or organization)

   4510 Lamesa Highway, Snyder, Texas                       79549
(Address of Principal Executive Offices)                 (Zip Code)

                                    ---------
  PATTERSON-UTI ENERGY, INC. AMENDED AND RESTATED 1997 LONG-TERM INCENTIVE PLAN
                                       and
                 1997 STOCK OPTION PLAN OF DSI INDUSTRIES, INC.
                           (Full title of the plan(s))

                                    ---------
                                Cloyce A. Talbott
                             Chief Executive Officer
                           Patterson-UTI Energy, Inc.
                    4510 Lamesa Highway, Snyder, Texas 79549
                                 (915) 573-1104
            (Name, address and telephone number of agent for service)

                                   Copies to:

Jonathan D. Nelson                                Thomas H. Maxfield, Esq.
Chief Financial Officer and                       Baker & Hostetler LLP
Vice President - Finance                          303 East Seventeenth Avenue,
4510 Lamesa Highway                               Suite 1100
Snyder, Texas  79549                              Denver, Colorado  80203


                                   ---------



                                     CALCULATION OF REGISTRATION FEE
===================================================================================================================================
Title of securities to   Amount to be registered       Proposed maximum            Proposed maximum aggregate       Amount of
      registered                   (1)             offering price per share(2)          offering price(2)       registration fee(2)
----------------------   -----------------------   ---------------------------     --------------------------   -------------------
                                                                                                    
Common Stock, par value
$.01 per share                   3,612,579                  $15.35                     $18,677,880              $4,670
===================================================================================================================================



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* Filed as a post-effective amendment to the Form S-8 Registration Statement
filed by Patterson-UTI Energy, Inc. ("Registrant") on May 8, 2001 in connection
with (i) the Patterson-UTI Energy, Inc. Amended and Restated 1997 Long-Term
Incentive Plan, as amended, (formerly known as the "UTI Energy Corp. Amended and
Restated 1997 Long-Term Incentive Plan") (referred to herein as the "1997 Long
Term Plan"); and (ii) the 1997 Stock Option Plan of DSI Industries, Inc.
(commonly referred to as the "Norton 1997 Stock Option Plan") (referred to
herein as the "Norton Plan") (collectively, the 1997 Long Term Plan and the
Norton Plan are referred to herein as the "Plans").

(1)      In addition to the 2,395,779 shares of common stock of Registrant, par
         value $.01 per share ("Common Stock"), previously registered by
         Registrant on May 8, 2001, this amount also consists of 1,216,800
         shares of Common Stock which may be sold upon the exercise of options
         granted by Registrant under the 1997 Long Term Plan on or after May 8,
         2001. The maximum number of shares sold upon the exercise of options
         granted on or after May 8, 2001 are subject to the Stockholder Rights
         Plan dated January 2, 1997 between Patterson Energy, Inc. and
         Continental Stock Transfer and Trust Company, as rights agent ("Rights
         Agreement"). Accordingly, pursuant to Rule 416 promulgated under the
         Securities Act of 1933, as amended ("Securities Act"), this
         Registration Statement covers, in addition to the number of shares
         stated above, an indeterminate number of shares which may be subject to
         grant or otherwise issuable after the operation of the Rights
         Agreement.

(2)      Calculated pursuant to Rule 457(c), based upon the average of the high
         and low sales price per share of Registrant's Common Stock on the
         NASDAQ National Market Issues Reports as of a date (July 20, 2001)
         within five (5) business days prior to filing this Registration
         Statement. All filing fees payable with respect to the registration of
         the 2,395,779 shares of Registrant's Common Stock on May 8, 2001 were
         paid in connection with the filing of the Form S-8 Registration
         Statement amended hereunder.



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                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

         The document(s) containing the information required by Part I will be
sent or given to employees as specified by Rule 428(b). Such documents are not
being filed with the Securities and Exchange Commission ("Commission") either as
part of this Registration Statement or as prospectuses or prospectus supplements
pursuant to Rule 424. Such documents and the documents incorporated by reference
in this Registration Statement pursuant to Item 3 of Part II to this Form S-8,
taken together, constitute a prospectus that meets the requirements of Section
10(a) of the Securities Act.





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                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

         All documents filed by the Registrant pursuant to Sections 13(a),
13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended (the
"Exchange Act"), subsequent to the date of the filing of this Registration
Statement and prior to the filing of a post-effective amendment indicating that
all securities registered hereunder have been sold, or that deregisters all
securities then remaining unsold, shall be deemed to be incorporated by
reference in this Registration Statement and to be a part hereof from the date
of the filing of such documents. The documents listed in (a) through (k) below
are incorporated by reference in this Registration Statement.

          (a)  The Annual Report on Form 10-K of the Registrant for the fiscal
               year ended December 31, 2000, filed with the Commission on March
               2, 2001;

          (b)  Registrant's Quarterly Report on Form 10-Q for the quarter ended
               March 31, 2001, filed with the Commission on May 7, 2001;

          (c)  Registrant's Current Report on Form 8-K dated February 5, 2001,
               and filed with the Commission on February 6, 2001;

          (d)  Registrant's Current Report on Form 8-K dated February 4, 2001,
               and filed with the Commission on February 16, 2001;

          (e)  Registrant's Current Report on Form 8-K dated March 27, 2001, and
               filed with the Commission on March 27, 2001;

          (f)  Registrant's Current Report on Form 8-K dated April 19, 2001 and
               filed with the Commission on April 23, 2001;

          (g)  Registrant's Current Report on Form 8-K dated May 8, 2001 and
               filed with the Commission on May 8, 2001;

          (h)  Registrant's Current Report on Form 8-K dated May 8, 2001 and
               filed with the Commission on July 23, 2001;

          (i)  All other reports filed by the Registrant or Patterson Energy,
               Inc. with the Commission pursuant to Section 13(a) or 15(d) of
               the Exchange Act since December 31, 2000;

          (j)  Description of the Registrant's Common Stock contained in the
               Registrant's Registration Statement on Form 8-A, which became
               effective with the Commission on November 2, 1993; and

          (k)  Description of the Registrant's Preferred Stock Purchase Rights
               contained in the Registrant's Registration Statement on Form B-A,
               which became effective on January 14, 1997.

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ITEM 4.  DESCRIPTION OF SECURITIES.

         Not Applicable.

ITEM 5.  INTEREST OF NAMED EXPERTS AND COUNSEL.

         The validity of the shares of the Registrant's Common Stock offered
hereby are being passed upon for the Registrant by Baker & Hostetler, LLP,
counsel to the Registrant. Members of that firm currently own 7,000 shares of
the Registrant's Common Stock.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         The Delaware General Corporation Law ("DGCL") allows a corporation to
indemnify directors, officers, employees and agents for costs and expenses
incurred by or in connection with an action, suit or proceeding brought by
reason of their position as a director, officer employee or agent. The person
indemnified must have acted in good faith and in a manner he reasonably believed
to be in or not opposed to the best interests of the corporation. The DGCL
provides that a corporation may advance payment of expenses under certain
circumstances. The DGCL further provides that the indemnification and
advancement of expenses provisions of the DGCL will not be deemed exclusive of
any other rights of indemnification or advancement of expenses to which
directors, officers, employees and agents may be entitled under bylaw,
agreement, vote of stockholders or disinterested directors or otherwise, both as
to action in such person's official capacity and as to action in another
capacity while holding such office.

         In addition to the general indemnification section, Delaware law
provides further protection for directors under Section 102(b)(7) of the DGCL.
This section allows a Delaware corporation to include in its certificate of
incorporation a provision that eliminates or limits the personal liability of a
director for monetary damages for breaches of the director's fiduciary duty of
care, provided that any such provision does not (in the words of the statute) do
any of the following:

         "eliminate or limit the liability of a director (i) for any breach of
         the director's duty of loyalty to the corporation or its stockholders,
         (ii) for acts or omissions not in good faith or which involve
         intentional misconduct or a knowing violation of law, (iii) under
         Section 174 of this Title [dealing with willful or negligent violation
         of the statutory provision concerning dividends and stock purchases and
         redemptions], or (iv) for any transaction from which the director
         derived an improper personal benefit. No such provision shall eliminate
         or limit the liability of a director for any act or omission occurring
         prior to the date when such provision becomes effective...."

         The DGCL further empowers the board of directors of the Registrant to
make other indemnification as authorized under the provisions of the restated
certificate of incorporation or bylaws, corporate resolution or agreement so
long as the indemnification is consistent with the DGCL.

         The Registrant's restated certificate of incorporation provides that,
to the fullest extent permitted by the DGCL, a director of the Registrant will
not be liable to the Registrant or its stockholders for monetary damages for
breach of fiduciary duty as a director. The Registrant's

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bylaws provide that to the extent that a director, officer, employee or agent of
the Registrant is successful on the merits of defense of a suit or proceeding
brought against him by reason of his position within the Registrant, he shall be
indemnified against expenses (including attorneys' fees) actually and reasonably
incurred in connection with such action. In other circumstances, a director,
officer employee or agent of the Registrant may be indemnified against expenses
(including attorneys' fees), judgments, fines and amounts paid in settlement
actually and reasonably incurred by him in connection with such action, suit or
proceeding if he acted in good faith and in a manner he reasonably believed to
be in and not opposed to the best interest of the Registrant, and, with respect
to a criminal action or proceeding, had no reasonable cause to believe his
conduct was unlawful; however, in an action or suit by or in the right of the
Registrant to procure a judgment in its favor, such person will not be
indemnified if he has been adjudged to be liable to the Registrant unless and
only to the extent that the Delaware Court of Chancery or the court in which
such action or suit was brought determines upon application that, despite the
adjudication of liability but in view of all the circumstances of the case, such
person is fairly and reasonably entitled to indemnity for such expenses which
the Court of Chancery or such other court deems proper. A determination that
indemnification is proper will be made by a majority of the Registrant's
disinterested directors, by independent legal counsel or by the stockholders of
the Registrant. The Registrant's bylaws also provide that the Registrant may
advance the payment of expenses and that the indemnification and advancement of
expense provisions of the bylaws are nonexclusive. The Registrant maintains
director and officer liability insurance covering director and officer
indemnification.

         In addition, in the Agreement and Plan of Merger between Patterson
Energy, Inc. and UTI Energy Corp. dated as of February 4, 2001, pursuant to
which UTI Energy Corp. ("UTI") merged with and into Patterson Energy, Inc.
("Patterson") with the Registrant as the surviving corporation ("Merger"), the
Registrant agreed to indemnify the former officers and directors of UTI from
liabilities arising out of actions or omissions in their capacity as such prior
to the effective time of the Merger, and advance reasonable litigation expenses
incurred in connection with such actions or omissions, to the full extent
permitted under UTI's certificate of incorporation and bylaws. Further, for a
period of six years after the effective time of the Merger, the Registrant will
provide UTI's officers and directors with an insurance and indemnification
policy that provides coverage through the effective time of the Merger; provided
that the maximum aggregate amount of premiums that the Registrant will be
required to pay to provide and maintain this coverage does not exceed $300,000
per year.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

       Not Applicable.

ITEM 8.  EXHIBITS.

       The Exhibits listed in the accompanying Exhibit Index are filed or
incorporated by reference as part of this Registration Statement.

ITEM 9.  UNDERTAKINGS.

A. The undersigned Registrant hereby undertakes:

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         (1) To file, during any period in which offers or sales are being made,
a post-effective amendment to this registration statement: (i) to include any
prospectus required by Section 10(a)(3) of the Securities Act; (ii) to reflect
in the prospectus any facts or events arising after the effective date of the
registration statement (or the most recent post-effective amendment thereof)
which, individually or in the aggregate, represent a fundamental change in the
information set forth in the registration statement. Notwithstanding the
foregoing, any decrease or increase in volume of securities offered (if the
total dollar value of the securities offered would not exceed that which was
registered) and any deviation from the low or the high end of the estimated
maximum offering range may be reflected in the form of a prospectus filed with
the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in
volume and price represent no more than a 20% change in the maximum aggregate
offering price set forth in the "Calculation of Registration Fee" table in this
Registration Statement; and (iii) to include any material information with
respect to the plan of distribution not previously disclosed in the registration
statement or any material change to such information in the registration
statement; provided, however, that clauses (i) and (ii) do not apply if the
information required to be included in a post-effective amendment by those
clauses is contained in periodic reports filed with or furnished to the
Commission by the Registrant pursuant to Section 13 or Section 15(d) of the
Securities Exchange Act of 1934, as amended ("Exchange Act") that are
incorporated by reference in this Registration Statement;

         (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof; and

         (3) To remove from registration by means of a post-effective amendment
any of the securities being registered that remain unsold at the termination of
the offering.

B. The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Exchange Act) that is
incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

C. Insofar as indemnification for liabilities arising under the Securities Act
may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the provisions described under Item 6 above or otherwise,
the Registrant has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a director, officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

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                                   SIGNATURES

         Pursuant to the requirements of the Securities Act, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Post-Effective
Amendment No. 1 to the Registration Statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Snyder, State of Texas,
on the 24th day of July, 2001.


                                                  PATTERSON-UTI ENERGY, INC.



                                                  By: /s/ CLOYCE A. TALBOTT
                                                     ---------------------------
                                                     Cloyce A. Talbott
                                                     Chief Executive Officer

       KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears
below constitutes and appoints Cloyce A. Talbott and A. Glenn Patterson, or
either of them, severally, as his/her attorney-in-fact and agent, with full
power of substitution and resubstitution, for him/her and in his/her name,
place, and stead, in any and all capacities, to sign any and all post-effective
amendments to this Registration Statement, and to file the same with all
exhibits hereto, and all other documents in connection herewith, with the
Commission, granting unto said attorney-in-fact and agent, and either of them,
full power and authority to do and perform each and every act and thing
requisite or necessary to be done in and about the premises, as fully to all
intents and purposes as he/she might or could do in person, hereby ratifying and
confirming all that said attorneys-in-fact and agents, or either of them, or
their or his substitutes, may lawfully do or cause to be done by virtue hereof.

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         Pursuant to the requirements of the Securities Act, this Post-Effective
Amendment No. 1 to the Registration Statement has been signed by the following
persons in the capacities indicated on the 24th day of July, 2001.



               SIGNATURE                                                    TITLE
               ---------                                                    -----
                                          
    /s/ Cloyce A. Talbott                    Chief Executive Officer, Director (principal executive officer)
---------------------------------            Vice President-Finance, Chief Financial Officer, Secretary,
        Cloyce A. Talbott



   /s/ Jonathan D. Nelson                    Treasurer, (principal financial officer and principal accounting
---------------------------------            officer)
       Jonathan D. Nelson


               *                             Chairman of the Board, Director
---------------------------------
        Mark S. Siegel


     /s/ A. Glenn Patterson                  President, Chief Operating Officer, Director
---------------------------------
        A. Glenn Patterson

                *                            Director
---------------------------------
      Spencer D. Armour, III

                *                            Director
---------------------------------
         Kenneth N. Berns

                *                            Director
---------------------------------
       Stephen J. DeGroat

                *                            Director
---------------------------------
         Vaughn E. Drum

                *                            Director
---------------------------------
         Robert C. Gist

                *                            Director
---------------------------------
         Curtis W. Huff

                *                            Director
---------------------------------
         Kenneth R. Peak

                *                            Director
---------------------------------
        Nadine C. Smith

*By:   /s/ Cloyce A. Talbott
    -----------------------------
           Cloyce A. Talbott
           Attorney-in-Fact


                                      II-6

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                                  EXHIBIT INDEX



     EXHIBIT
     NUMBER             EXHIBIT DESCRIPTION
     ------             -------------------
              
       4.1       Restated Certificate of Incorporation(1)

       4.2       Bylaws(2)

       4.3       Stockholder Rights Plan dated January 2, 1997 between Patterson Energy, Inc.
                 and Continental Stock Transfer & Trust Company, as rights agent(3)

       4.4       1997 Stock Option Plan of DSI Industries, Inc.

       4.5       Patterson-UTI Energy,Inc. Amended and Restated 1997 Long-Term Incentive Plan

       4.5.1     Amendment No. 1 to the Patterson-UTI Energy, Inc. Amended and Restated 1997
                 Long-Term Incentive Plan adopted by the Board of Directors of UTI Energy
                 Corp. on April 26, 1999

       4.5.2     Amendment No. 2 to the Patterson-UTI Energy, Inc. Amended and Restated 1997
                 Long-Term Incentive Plan adopted by the Board of Directors of UTI Energy
                 Corp. on April 27, 2000

       5.1       Opinion of Baker & Hostetler LLP

      15.1       Awareness Letter of PricewaterhouseCoopers LLP

      23.1       Consent of Independent Accountants, PricewaterhouseCoopers LLP

      23.2       Consent of M. Brian Wallace, Independent Petroleum Engineer

      23.3       Consent of Baker & Hostetler LLP(4)

      24.1       Power of Attorney(5)


(1)      Incorporated herein by reference to Item 7, "Financial Statements and
         Exhibits" to Current Report on Form 8-K filed with the Commission on
         May 8, 2001.

(2)      Incorporated herein by reference to Item 27, "Exhibits" to Amendment
         No. 2 to Registration Statement on Form SB-2 (File No. 33-68058-FW);
         filed October 28, 1993.


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(3)      Incorporated herein by reference to Item 2, "Exhibits" to Registration
         Statement on Form 8-A; filed January 14, 1997.

(4)      Included in Opinion of Baker & Hostetler, LLP filed as Exhibit 5.1.

(5)      Included in the signature page to this Post-Effective Amendment No. 1
         to the Registration Statement.