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                                                                     Exhibit 4.2
                                         English Translation of Chinese Original

            RISK OPERATION SERVICE BUSINESS ASSETS TRANSFER AGREEMENT

                                 By and between

                      CHINA NATIONAL PETROLEUM CORPORATION

                                       And

                           PETROCHINA COMPANY LIMITED

                                 August 23, 2007


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                                TABLE OF CONTENTS
<TABLE>
<S>                                                                           <C>
ARTICLE 1  DEFINITIONS.....................................................    3
ARTICLE 2  DELIVERY OF ASSETS..............................................    5
ARTICLE 3  TRANSFER OF ASSETS..............................................    5
ARTICLE 4  CLOSING.........................................................    5
ARTICLE 5  CLOSING CONDITIONS..............................................    6
ARTICLE 6  POST-EXECUTION OBLIGATIONS OF PARTY.............................    7
ARTICLE 7  REPRESENTATIONS, WARRANTIES AND COVENANTS OF PARTY A............    7
ARTICLE 8  REPRESENTATIONS AND WARRANTIES OF PARTY B.......................    8
ARTICLE 9  EMPLOYEES.......................................................    8
ARTICLE 10 ACCESS TO INFORMATION...........................................    8
ARTICLE 11 FORCE MAJEURE...................................................    8
ARTICLE 12 COMMUNICATIONS..................................................    9
ARTICLE 13 GOVERNING LAW AND DISPUTE RESOLUTION............................    9
ARTICLE 14 OTHER PROVISIONS................................................   10
EXHIBIT 1  FURTHER REPRESENTATIONS, WARRANTIES AND COVENANTS OF PARTY A....   11
EXHIBIT 2  SCOPE OF THE RISK OPERATION SERVICE BUSINESS ASSETS.............   12
</TABLE>


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            RISK OPERATION SERVICE BUSINESS ASSETS TRANSFER AGREEMENT

     This Risk Operation Service Business Assets Transfer Agreement (this
"Agreement") is entered into this 23rd day of August, 2007 in Beijing by and
between CHINA NATIONAL PETROLEUM CORPORATION ("Party A"), with its enterprise
legal person business license number being 1000001001043 and registered address
being at Liupukang, Xicheng District, Beijing, and PETROCHINA COMPANY LIMITED
("Party B"), with its enterprise legal person business license number being
1000001003252 and registered address being at 16 Andelu, Dongcheng District,
Beijing.

     Whereas,

     (i)  Party B is a joint stock company incorporated on November 5, 1999
          under the laws of the People's Republic of China (the "PRC") , and its
          H shares and ADSs are currently listed and traded on the Stock
          Exchange of Hong Kong Limited and on the New York Stock Exchange, Inc.
          respectively. Party A holds 88.21% of the share capital of Party B and
          therefore is the controlling shareholder of Party B; and

     (ii) Party A agrees to transfer to Party B, and Party B agrees to purchase
          from Party A, the assets (including liabilities) of Party A's risk
          operation service business, subject to the terms and conditions of
          this Agreement.

     Party A and Party B hereby reach agreement as follows:

                              ARTICLE 1 DEFINITIONS

     1.1  For purposes of this Agreement, unless the context otherwise
          specifies, terms in this Agreement and the exhibits hereto shall have
          the meanings set forth below:

<TABLE>
<S>                  <C>
"Agreement" or       refers to this Risk Operation Service Business Assets
this "Agreement"     Transfer Agreement dated August 23, 2007 by and between the
                     parties hereto;

"Party A"            refers to China National Petroleum Corporation and its
                     subsidiaries, branches and other affiliated entities;
                     unless otherwise required by the context, the term "Party
                     A" shall include all the assets and business of Party A;

"Party B"            refers to PetroChina Company Limited and its subsidiaries,
                     branches and other affiliated entities; unless otherwise
                     required by the context, the term "Party B" shall include
                     all the assets and business of Party B;
</TABLE>


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<TABLE>
<S>                  <C>
"Risk Operation      refers to the full-range risk operation services discussed
Service Business"    hereunder provided to Party B's development and production
                     operation in the hard-to-exploit blocks, at Party A's
                     expense and risk, by such second-level entities of Xinjiang
                     Petroleum Administration Bureau as less-profitable oilfield
                     development companies, cooperative development and oil
                     extraction operation areas, and the Oil and Gas Cooperative
                     Development Company of Tuha Petroleum Exploration and
                     Development Headquarters;

"Risk Operation      refers to the assets to be transferred hereunder, which are
Service Business     generated by the Risk Operation Service Business of such
Assets"              second-level entities of Xinjiang Petroleum Administration
                     Bureau as less-profitable oilfield development companies,
                     cooperative development and oil extraction operation areas,
                     and the Oil and Gas Cooperative Development Company of Tuha
                     Petroleum Exploration and Development Headquarters,
                     including the assets as set forth in Exhibit 2 hereto;

"Closing"            has the meaning set forth in Article 4 hereof;

"Closing Date"       the later of August 23, 2007, or the date on which all the
                     conditions specified in Article 5 below have been
                     satisfied;

"Base Date"          refers to December 31, 2006, the date on which the assets
                     appraisal is conducted for the purposes of the transfer
                     contemplated hereunder;

"Audit Reports"      refers to the Special Audit Report on Oil and Gas
                     Cooperative Development Company of Tuha Oil Exploration and
                     Development Headquarters (Zhong Tian Yun [2007] Pu Zi No.
                     04212) and the Special Audit Report on the Risk Operation
                     Service Business of Xinjiang Petroleum Administration
                     Bureau (Zhong Tian Yun [2007] Pu Zi No. 04213) in each
                     case, dated June 20, 2007 and issued by Zhongtianyun
                     Accountants Limited for the purposes of the transfer
                     contemplated hereunder; and

"Appraisal Report"   refers to the Assets Appraisal Report (Zhong Qi Hua Ping
                     Bao Zi(2007) No. 195-1 and No. 195-2) dated June 20, 2007
                     issued by China Enterprise Appraisal Co., Ltd.
</TABLE>

     1.2  Unless otherwise specified herein, for the purposes of this Agreement,

          (a)  All references herein to a party shall include the successors
               thereof;

          (b)  All references herein to Articles or Schedule shall refer to
               Articles or Schedules of this Agreement;

          (c)  This Agreement shall be construed to refer to this Agreement as
               extended, amended, modified or supplemented from time to time;

          (d)  Headings used herein are for convenience only, and shall not in
               any way affect the meaning or performance of this Agreement; and


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          (e)  Any subsidiary or affiliated entity of Party A shall not include
               Party B or any of its subsidiaries or affiliated entities.

                          ARTICLE 2 DELIVERY OF ASSETS

     2.1  Subject to the terms and conditions of this Agreement, Party A shall
          deliver to Party B, and Party B shall take delivery from Party A of,
          the Risk Operation Service Business Assets and any and all the
          existing and future rights attached thereto, in reliance on Party A's
          relevant representations, warranties and covenants contained herein.

     2.2  The Risk Operation Service Business Assets are described in greater
          detail in Exhibit 2 hereto.

                          ARTICLE 3 TRANSFER OF ASSETS

     The parties hereto agree that the consideration for the Risk Operation
Service Business Assets shall be RMB 1,652,279,200, as determined based on the
Appraisal Report dated 31 December, 2006 prepared by China Enterprise Appraisal
Co., Ltd. In the event the net assets generated by the Risk Operation Service
Business for the period from 1 January 2007 to 31 August 2007 as shown in the
management accounts for that period is higher than the value of the net assets
of the Risk Operation Service Business as at 31 December 2006, Party B shall pay
such difference to Party A in cash.

                                ARTICLE 4 CLOSING

     4.1  Date of Closing

          The closing of the assets transfer contemplated hereunder (the
          "Closing") shall occur on the later of August 23, 2007 or the date on
          which all the conditions set forth in Article 5 herein below are
          satisfied (either the "Closing Date").

     4.2  At the Closing, Party A shall:

          4.2.1 deliver to Party B:

               (i)  the Risk Operation Service Business Assets and any and all
                    the certificates, deeds, operating licenses, title documents
                    and other instruments that evidence any and all the title
                    and operating rights to and in the Risk Operation Service
                    Business Assets are vested with Party B, including but not
                    limited to, land use certificates, building title
                    certificates, accounting books and records, property
                    insurance policies and receipts for insurance premium
                    payment;


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               (ii) any and all the third party consents necessary for Party A's
                    transfer to Party B of the Risk Operation Service Business
                    Assets, including but not limited to, consents from relevant
                    creditors and consents from relevant governmental
                    authorities; and

               (iii) any and all the effective contracts, books, certificates,
                    records and other instruments (including financial records)
                    possessed or controlled by Party A in connection with the
                    Risk Operation Service Business Assets, and

          4.2.2 allow Party B to take possession of the Risk Operation Service
               Business Assets.

     4.3  Party B shall obtain the Risk Operation Service Business Assets as
          from the Closing Date (inclusive). As from the Closing Date, Party B
          shall become the sole owner of the Risk Operation Service Business
          Assets and have all the operating rights in and to the Risk Operation
          Service Business Assets.

     4.4  Unless otherwise specified herein, any and all the profits, interests,
          creditor's rights, debts and other rights and obligations generated by
          the Risk Operation Service Business Assets prior to the Closing Date
          shall be exercised and performed by Party A.

     4.5  In case Party A fails to fully comply with Section 4.2 above, Party B
          may elect to consummate the Closing to the extent practicable without
          any prejudice to any other remedies and rights available to it under
          this Agreement and otherwise.

                          ARTICLE 5 CLOSING CONDITIONS

     5.1  The Closing shall be subject to the satisfaction of all the following
          preconditions:

          (a)  Party B has completed its due diligence with respect to the
               status of the Risk Operation Service Business Assets;

          (b)  Party A has obtained from its creditors and any other relevant
               third parties any and all the necessary consents for Party A's
               transfer of the Risk Operation Service Business Assets to Party
               B;

          (c)  there has been no material adverse change to the operation or
               technical performance of the Risk Operation Service Business; and


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          (d)  As at the Closing Date, Party A's representations, warranties and
               covenants contained herein shall remain true, accurate, complete
               and effective.

     5.2  The parties hereto shall make all reasonable efforts to ensure that
          all the conditions set forth in Section 5.1 above will have been
          satisfied by August 23, 2007. Where any condition set forth in Section
          5.1 fails to be satisfied by August 23, 2007 for any reason on the
          part of Party A, Party B shall have the right to terminate this
          Agreement at its discretion.

     5.3  Each of the parties hereto agrees that where any regulatory authority
          in the jurisdiction in which its shares are listed and relevant PRC
          governmental authorities raise certain conditions in order to approve
          the transfer of the Risk Operation Service Business Assets as
          contemplated hereunder, the parties will negotiate corresponding and
          appropriate amendments to this Agreement and other relevant Closing
          conditions. Where no agreement fails to be reached through such
          negotiations and the performance of this Agreement will result in
          either Party A or Party B violating any PRC law and/or relevant
          listing rules, either Party A or Party B, as the case may be, shall
          have the right to terminate this Agreement at its discretion.

                  ARTICLE 6 POST-EXECUTION OBLIGATIONS OF PARTY

     6.1  Party A undertakes that it will use its best efforts to provide Party
          B with any and all materials and assistance in connection with the
          operation and maintenance of any Risk Operation Service Business
          reasonably requested by Party B.

     6.2  Without the consent of Party B, Party A may not make use of or
          disclose or release to any third party any information relating to any
          Risk Operation Service Business Assets except where the information is
          otherwise available in the public domain or where disclosure is
          required by the orders of a court having competent jurisdiction or the
          relevant regulatory authorities.

         ARTICLE 7 REPRESENTATIONS, WARRANTIES AND COVENANTS OF PARTY A

     7.1  Party A hereby makes the representations, warranties and covenants in
          accordance with the terms set forth under Exhibit 1 ("Warranties") to
          Party B, and acknowledges that the execution by Party B of this
          Agreement is based on the reliance of Party B on such Warranties.

     7.2  Each Warranty of Party A set forth in Exhibit 1 shall be severable and
          independent, and none of other provisions in this Agreement or the
          exhibits hereto may limit such Warranties.

     7.3  Party A hereby further undertakes to indemnify Party B in all for and
          against all losses or liabilities, including but not limited to, the
          decrease of the value of


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          any Risk Operation Service Business Assets, arising from breaches of
          any Warranties by Party. In the event of any breach by Party A of
          Article 1 or 2 of Exhibit 1 hereto, Party B shall have the right to
          terminate this Agreement.

     7.4  Party A shall promptly inform Party B in writing of any violations of
          the Warranties or any matters not consistent with the Warranties it
          becomes aware of before or after the Closing.

               ARTICLE 8 REPRESENTATIONS AND WARRANTIES OF PARTY B

     Party B hereby represents and warrants to Party A that from the date of
this Agreement to the Closing Date:

     8.1  Party B is a company limited by shares duly organized, validly
          existing and in good standing under the laws of the PRC and has
          statutory corporate rights.

     8.2  Party B has all necessary power and authority to enter into and
          perform this Agreement.

     8.3  The execution and performance of this Agreement by Party B does not
          violate its articles of association or any applicable laws or
          regulations.

     8.4  This Agreement constitutes a valid and binding obligation of Party B.

                               ARTICLE 9 EMPLOYEES

     Party B may conduct its employment management in its own discretion for the
purpose of continuing operation of the Risk Operation Service Business Assets,
including employing the former employees engaged by Party A for the Risk
Operation Service Business Assets.

                        ARTICLE 10 ACCESS TO INFORMATION

     From the date of this Agreement, Party A shall afford Party B and any
persons authorized by Party B and shall cause such person to be afforded access
to all materials regarding the Risk Operation Service Business Assets, and all
books, title instruments, contracts, records and any other documents regarding
the Risk Operation Service Business Assets, and the executive officers and
employees of Party A shall promptly furnish such materials and explanations with
respect thereto to any such persons.

                            ARTICLE 11 FORCE MAJEURE

     If a party has been prevented from performing all or part of its
obligations provided in this Agreement because of an event of Force Majeure,
including earthquake, typhoon, flood, fire, war and any governmental
interference, or change of circumstances, it shall immediately notify the other
Party in writing, and shall provide details of the event of Force Majeure or
change of circumstances, as well as valid evidence supporting its inability to
perform all or part of its obligations hereunder or the reasons for the delayed
performance, within seven (7) days following the occurrence of such an event.
The parties shall negotiate to terminate this Agreement, partially release or
delay the performance of the affected obligations, according to the influence of
such an event on the performance of this Agreement.


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                            ARTICLE 12 COMMUNICATIONS

     Notices or other communications required to be given by any party pursuant
to this Agreement shall be written in Chinese and sent by personal delivery or
in registered mail or facsimile to the address/fax number of the other party set
forth below. The dates on which notices shall be deemed to have been effectively
given shall be determined as follows:

     (i)  Notices given by personal delivery shall be deemed effectively given
          on the date of personal delivery;

     (ii) Notices given in a registered mail shall be deemed effectively given
          on the seventh day after the date on which they were mailed (as
          indicated by the postmark), excluding public holidays;

     (iii) Notices given by facsimile shall be deemed effectively given upon the
          completion of transmission. The party sending notices shall provide
          the electronic answerbacks produced by the facsimile machine it has
          received for the notices it sends to the other party in order to prove
          the complete transmission of such notices to the other party.

     If to Party A:

          China National Petroleum Corporation
          Liupukang, Xicheng District
          Beijing 100724
          Fax: 010-6209 4205

     If to Party B:

          PetroChina Company Limited
          16 Ande Road, Dongcheng District
          Beijing 100011
          Fax: 010-8488 6001

                 ARTICLE 13 GOVERNING LAW AND DISPUTE RESOLUTION

     13.1 This Agreement shall be governed by and construed in accordance with
          the laws of the PRC.

     13.2 Any dispute arising from, out of or in connection with this Agreement
          shall be settled through friendly consultations between the parties.
          If the dispute cannot be settled through consultations, either party
          may refer such dispute to the Beijing Arbitration Commission. Such
          dispute shall be finally settled by arbitration in accordance with the
          then effective rules of arbitration of the Beijing Arbitration
          Commission. The arbitral award is final and binding upon


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          both parties.

                           ARTICLE 14 OTHER PROVISIONS

     14.1 The parties shall be solely responsible for their own costs and
          expenses arising from the transfer of the Risk Operation Service
          Business Assets hereunder according to the applicable laws.

     14.2 Upon the Closing of the transfer of the Risk Operation Service
          Business Assets, except with respect to the surviving company, Party A
          shall finish all required change or cancellation formalities with the
          competent administration of industry and commerce and tax authorities.

     14.3 The invalidity, illegality or unenforceability in any respect of any
          term or other provision of this Agreement may not affect or prejudice
          the legality, validity and enforceability of all other terms and
          provisions of this Agreement.

     14.4 This Agreement together with any documents referred to herein shall
          constitute an entire agreement between the parties hereto. The parties
          clearly represent that any amendment to this Agreement shall be
          invalid unless in writing.

     14.6 This Agreement shall have come into effect upon the execution and
          affixing seals by the representatives of each party.

Party A

CHINA NATIONAL PETROLEUM CORPORATION

Authorized representative: Wen Qingshan (signature and seal of Party A)

Party B:

PETROCHINA COMPANY LIMITED

Authorized representative: Zhou Mingchun (signature and seal of Party B)


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     EXHIBIT 1 Further Representations, Warranties and Covenants of Party A

1. CORPORATE MATTERS

1.1  Party A is wholly state-owned company duly organized and validly existing
     under the laws of the PRC and has full and legal rights to own its assets
     and operate its business.

1.2  All the copies of the business license, articles of association and other
     documents of Party A provided to Party B are accurate and complete, and
     conform with the original copies of such documents.

1.3  Party A has all necessary power and authority to execute this Agreement and
     perform its obligations hereunder.

1.4  This Agreement and any other documents to be executed by Party A pursuant
     to this Agreement shall constitute the valid and binding obligations of
     Party A, which are enforceable in accordance with the relevant terms.

2. APPROVALS

2.1  The transfer of the Risk Operation Service Business Assets by Party A to
     Party B shall be conducted in accordance with the PRC law.

2.2  Upon the Closing Date, all governmental approvals required for the transfer
     of the Risk Operation Service Business Assets, including but not limited
     to, the required approval for the change of land use rights certificates
     and title certificates, shall have been obtained, and Party A does not
     receive any notice that such approvals have been cancelled.

2.3  Party A has been granted all necessary authorization for the execution and
     performance of this Agreement.

2.4  The execution and performance of this Agreement does not violate any
     applicable laws or regulations.

3. OWNERSHIP AND CONDITIONS OF ASSETS

3.1  Except as otherwise indicated, none of the Risk Operation Service Business
     Assets is subject to any encumbrance of any form. In the event of any legal
     proceedings in respect of financial guarantees or any other disputes
     arising prior to the Closing Date, such proceedings or disputes shall be
     assumed by the appropriate unlisted companies, i.e. Xinjiang Petroleum
     Administration Bureau or Tuha Petroleum Exploration & Development
     Headquarters. Details regarding the Risk Operation Service Business Assets
     set forth in Exhibit 2 are true, complete and accurate in all respects.


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          EXHIBIT 2 Scope of the Risk Operation Service Business Assets

The Risk Operation Service Business Assets cover the principal business of such
second-level entities of Xinjiang Petroleum Administration Bureau as
less-profitable oilfield development companies, cooperative development and oil
extraction operation areas, and the Oil and Gas Cooperative Development Company
of Tuha Petroleum Exploration and Development Headquarters, including but not
limited to, assets relating to the Risk Operation Business and the assets,
liabilities and interests associated therewith, which in particular, include the
following assets:

1.   such assets as the buildings and other structures, cash, bank deposits and
     accounts, inventories, receivables, machinery and equipment and ancillary
     devices and facilities owned by Party A or any entity forming a part of the
     Risk Operation Service Business;

2.   the rights and obligations under the contracts and agreements (including
     any amendments and supplements thereto) executed by Party A in respect of
     the Risk Operation Service Business Assets, including title to buildings
     and guarantees with respect to such contracts and agreements;

3.   if transferrable in accordance with applicable laws, all the rights under
     any and all the permits, licenses, approval certificates, certificates,
     power of attorney, and any other similar documents possessed or owned by
     Party A or any entity forming a part of the Risk Operation Service
     Business;

4.   claims, set-off rights or any other similar rights of Party A or any entity
     forming a part of the Risk Operation Business Assets, in each case,
     relating to or arising from the Risk Operation Service Business Assets; and

5.   business records, accounting records, operating records, operating data,
     operating statistical data, manuals, maintenance handbooks, training
     handbooks and relevant technical records, technical documentation,
     technical data, technical drawings, technical handbooks, technical books,
     project research and development records and any other know-how, whether
     saved in written, electronic or any other media.

Any other assets set forth in the Appraisal Report. The parties hereto agree
that where they have any disagreement on the understanding of the Risk Operation
Service Business Assets set forth in this Schedule, the contents of the
Appraisal Report shall prevail.


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