untitled THIS CIRCULAR IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION If you are in any doubt as to any aspect of this circular or as to the action to be taken, you should consult your licensed securities dealer, bank manager, solicitor, professional accountant or other professional adviser. If you have sold or transferred all your shares in China Oilfield Services Limited, you should at once hand this circular, together with the enclosed form of proxy, to the purchaser or transferee or to the bank, licensed securities dealer or other agent through whom the sale or transfer was effected for transmission to the purchaser or transferee.

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this circular, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this circular.



(Incorporated in the People's Republic of China as a joint stock limited liability company)

(Stock Code: 2883) PROPOSED RE-ELECTION OF DIRECTORS AND SUPPLEMENTAL NOTICE OF AGM

Please refer to the "Definitions" section of this circular for the meanings of the capitalised terms used in this front cover.

The initial notice of the annual general meeting of the Company to be held at Room 504, CNOOC Plaza, 25

Chaoyangmen North Avenue, Dongcheng District, Beijing, the PRC on Tuesday, 2 June 2015 at 10:00 a.m. was set out in the Initial Notice. A supplemental notice of AGM dated 21 May 2015 is set out on pages 8 to

10 of this circular. By such supplemental notice of AGM, an additional resolution will be proposed for Shareholders' consideration at the AGM, in relation to the proposed re-election of directors, details of which are set out in this circular.

A revised form of proxy for use at the AGM, which contains an additional resolution to be proposed at the AGM, is sent together with this circular in which the supplemental notice of AGM is set out. Any shareholder who has not yet lodged the First Proxy Form with the Company is requested to lodge the Second Proxy Form if he/she wishes to appoint proxies to attend the AGM on his/her behalf. In such case, the First Proxy Form should not be lodged with the Company. Whether or not you intend to attend the AGM, you are requested to complete the revised proxy form in accordance with the instructions printed thereon and return the same to the registrar of H Shares of the Company, Computershare Hong Kong Investor Services Limited at 17M Floor, Hopewell Centre, 183 Queen's Road East, Wanchai, Hong Kong as soon as possible and in any event not less than 24 hours before the time appointed for the holding of the relevant meeting or any adjournment thereof (as the case may be). Completion and return of the proxy form will not prevent you from attending and voting in person at the meeting(s) or any adjournment thereof should you so wish.

21 May 2015

CONTENTS

Page

Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Letter from the Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Appendix - Particulars of Directors Proposed to be Re-elected . . . . . . . . . . . . . . . . 6 Supplemental Notice of Annual General Meeting . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

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DEFINITIONS

In this circular, the following expressions have the following meanings, unless the context otherwise requires:

"AGM" the Annual General Meeting of the Company to be held at Room 504, CNOOC Plaza, 25 Chaoyangmen North Avenue, Dongcheng District, Beijing, the PRC, at 10:00 a.m. on Tuesday, 2 June 2015, or any adjournment thereof;
"Board" the board of Directors;
"Company" (China Oilfield Services Limited), a joint stock company incorporated in the PRC with limited liability, the A-Shares of which are listed on the Shanghai Stock Exchange and the H-Shares of which are listed on the main board of the Stock Exchange;
"Directors" the directors of the Company;
"First Proxy Form" the form of proxy sent together with the Initial Notice of AGM to the holder of H Shares;
"H Share(s)" overseas listed foreign share(s) of nominal value of RMB1.00 each in the share capital of the Company which are listed on the Main Board of the Stock Exchange and subscribed for in HK dollars;
"Hong Kong" the Hong Kong Special Administrative Region of the
PRC;
"Initial Notice" the initial notice of AGM dated 17 April 2015, which convenes the AGM;
"Latest Practicable Date" 20 May 2015, being the latest practicable date prior to the printing of this circular for ascertaining certain information contained therein;
"Listing Rules" the Rules Governing the Listing of Securities on the
Stock Exchange;
"PRC" the People's Republic of China;
"RMB" Renminbi, the lawful currency of the PRC;
"Second Proxy Form" the revised form of proxy sent together with this circular of the Company;
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DEFINITIONS


"Shareholder(s)" the holder(s) of the Share(s) of the Company; "Stock Exchange" The Stock Exchange of Hong Kong Limited;
"Supplemental Notice" the supplemental notice of AGM dated 21 May 2015,
which forms part of this circular.
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LETTER FROM THE BOARD



(Incorporated in the People's Republic of China as a joint stock limited liability company)

(Stock Code: 2883)

Board of Directors:

Liu Jian (Chairman)* Li Yong
Li Feilong
Zeng Quan*
Tsui Yiu Wa**
Fong Wo, Felix**
Law Hong Ping, Lawrence**

* Non-executive Director

** Independent non-executive Director

To the Shareholders:

Dear Sir or Madam,

Legal address in the PRC:

3-1516 Hebei Road Haiyang New and
Hi-Tech Development Zone
Tanggu, Tianjin
The PRC

Registered Office in Hong Kong:

65/F, Bank of China Tower
1 Garden Road
Hong Kong
21 May 2015

PROPOSED RE-ELECTION OF DIRECTORS AND SUPPLEMENTAL NOTICE OF AGM 1. INTRODUCTION

Reference is made to the Initial Notice of the Company dated 17 April 2015, which notice contains certain resolutions proposed to be considered and, if thought fit, approved by Shareholders at the AGM.
The purpose of this circular is to provide you with details of the proposed re-election of Directors, which is proposed to be considered and, if thought fit, approved by Shareholders at the AGM, the proposed resolution relating to which is set out in the Supplemental Notice.

2. RE-ELECTION OF DIRECTORS

On 20 May 2015, China National Offshore Oil Corporation (which is the holder of
50.52% shareholding of the Company) gave a notice to the Company requesting for the inclusion in the agenda of the AGM of an additional proposed resolution relating to the re-election of Directors set out in this circular.
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LETTER FROM THE BOARD


As at the Latest Practicable Date, the executive Directors were Mr. Li Yong and Mr. Li Feilong; the non-executive Directors were Mr. Liu Jian (Chairman) and Mr. Zeng Quan; and the independent non-executive Directors were Mr. Tsui Yiu Wa, Mr. Fong Wo, Felix and Mr. Law Hong Ping, Lawrence.
At the Annual General Meeting, Mr. Li Yong and Mr. Liu Jian will retire as executive Director and non-executive Director, respectively, and being eligible, have offered themselves to be re-elected at the Annual General Meeting for another three-year term commencing on the date of the Annual General Meeting.
The biographical and other details of Mr. Li Yong and Mr. Liu Jian are set out in
Appendix to this circular.

3. AGM

A supplemental notice of the AGM to be held as originally scheduled at Room 504, CNOOC Plaza, 25 Chaoyangmen North Avenue, Dongcheng District, Beijing, the PRC on Tuesday, 2 June 2015 at 10:00 a.m. is set out on pages 8 to 10 of this circular. Please refer to the Initial Notice for details of the other resolutions to be proposed at the AGM, the voting arrangements, the poll procedure at the AGM and other related matters.
The accumulative voting system may be adopted by the Company pursuant to the provisions of the Articles or a resolution of the general meeting for the election of directors at the general meeting. Under the accumulative voting system, each share shall be entitled to votes equivalent to the number of directors to be elected for the election of directors at the general meeting, and shareholders may consolidate their voting rights when casting a vote.
Whether or not you intend to attend the AGM, you are requested to complete the Second Proxy Form in accordance with the instructions printed thereon and return the same to the registrar of H Shares of the Company, Computershare Hong Kong Investor Services Limited at 17M Floor, Hopewell Centre, 183 Queen's Road East, Wanchai, Hong Kong as soon as possible and in any event not less than 24 hours before the time appointed for the holding of the relevant meeting or any adjournment thereof (as the case may be). Completion and return of the proxy form will not prevent you from attending and voting in person at the meeting(s) or any adjournment thereof should you so wish.

4. SECOND PROXY FORM

Since the First Proxy Form which was sent together with the Initial Notice does not contain the proposed additional resolution relating to the proposed re-election of Directors as set out in this circular, the Second Proxy Form is sent together with this circular of which the Supplemental Notice forms part. Any Shareholder who has not yet lodged the First Proxy Form with the Company is requested to lodge the Second Proxy Form if he/she wishes to appoint proxies to attend the AGM on his/her behalf. In such case, the First Proxy Form should not be lodged with the Company. Shareholders are requested to complete and return the Second Proxy Form in accordance with the instructions printed thereon to the registrar of H Shares of the Company, Computershare Hong Kong Investor Services Limited
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LETTER FROM THE BOARD


at 17M Floor, Hopewell Centre, 183 Queen's Road East, Wanchai, Hong Kong not less than
24 hours before the time appointed for the holding of the relevant meeting or any adjournment thereof (as the case may be).
Any Shareholder who has already lodged the First Proxy Form with the Company should note that:
(i) if no Second Proxy Form is lodged with the Company, the First Proxy Form will be treated as a valid proxy form lodged by him/her if correctly completed. The proxy so appointed by the Shareholder will be entitled to vote at his/her discretion or to abstain from voting on any resolution properly put to the AGM, including the resolution for, among other matters, the proposed re-election of Directors, as set out in the Supplemental Notice.
(ii) if the duly completed and signed Second Proxy Form is lodged with the Company
24 hours prior to the time appointed for holding the AGM (the "Closing Time"), the Second Proxy Form will revoke and supersede the First Proxy Form previously lodged by him/her. The Second Proxy Form will be treated as a valid proxy form lodged by the Shareholder if it is duly completed and signed and returned in accordance with the instructions printed thereon.
(iii) if the duly completed and signed Second Proxy Form is lodged with the Company after the Closing Time, the Second Proxy Form will be invalid. However, it will revoke the First Proxy Form previously lodged by the Shareholder, and any vote that may be cast by the purported proxy (whether appointed under the First Proxy Form or the Second Proxy Form) will not be counted in any poll which will be taken on any proposed resolution. Accordingly, Shareholders are advised not to lodge the Second Proxy Form after the Closing Time. In such case, if any Shareholder wishes to vote at the AGM, he/she will have to attend in person and vote at the AGM himself/herself.

5. RECOMMENDATION

The Directors believe that the proposals for the re-election of Directors are in the best interests of the Company and its Shareholders. Accordingly, the Directors recommend the Shareholders to vote in favour of the above resolutions to be proposed at the AGM.
Yours faithfully
For and on behalf of

CHINA OILFIELD SERVICES LIMITED Yang Haijiang

Company Secretary

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APPENDIX PARTICULARS OF DIRECTORS PROPOSED TO BE RE-ELECTED

The biographical details of the Directors proposed to be re-elected at the Annual

General Meeting are set out as follows:

Executive Director Mr. Li Yong, Chinese, male, born in 1963, Executive Director, Chief Executive Officer and the President of the Company. He graduated from Southwest Petroleum Institute with a Bachelor in Petroleum Engineering in 1984. Mr. Li obtained a master degree in Oil Economics from the Scuola E Mattei of Italy in 1989 and an MBA from Peking University in 2001. Since August 2010, Mr. Li has been the Executive Director, Chief Executive Officer and President of the Company. From April 2009 to August 2010, he served as Executive Director and President of the Company. From May 2006 to April 2009, he served as Executive Director, Executive Vice President and Chief Operating Officer of the Company. From October 2005 to May 2006, Mr. Li was Executive Vice President and Chief Operating Officer of the Company. From 2003 to 2005, Mr. Li served as Deputy General Manager of CNOOC (China) Ltd. - Tianjin Branch. He was Director of Drilling and Completion Well of CNOOC Ltd from 1999 to 2003. Between 1993 and 1999, Mr. Li was Head of Comprehensive Technology Division and Head of Well Testing Division of Exploration Department of CNOOC. Mr. Li joined CNOOC in 1984 and had served in various positions, including Assistant Engineer and Engineer at China Offshore Oil Exploration Project Planning Company, CNOOC Operational Department, and has worked in the oil and natural gas industry for over 31 years.

There is no director service contract between the Company and Mr. Li. Mr. Li will not receive any director fee and his term of directorship is subject to retirement by rotation and re-election at the annual general meeting of the Company in accordance with the Articles. Other emoluments received by Mr. Li Yong as a senior management of the Group will be determined according to the relevant national requirements and requirements of the Company. The Company will disclose Mr. Li's emolument in the Company within the reporting period in the Company's annual report.

Non-Executive Director Mr. Liu Jian, Chinese, male, born in 1958, Chairman and a Non-Executive Director of the Company. He graduated from Huazhong University of Science and Technology with a Bachelor of Science degree and received his MBA degree from Tianjin University in 2000. Mr. Liu is a senior engineer. Mr. Liu first joined the Group in 1982 and has over 33 years of experience in the oil and gas industry. He served as the manager of CNOOC Bohai Corporation Oil Production Company, a subsidiary of the Group, the Deputy General Manager of the Tianjin Branch of CNOOC China Limited, the General Manager of the Zhanjiang Branch of CNOOC China Limited, the Senior Vice President and General Manager of the Development and Production Department of CNOOC Limited, the director of CNOOC China Limited, CNOOC International Limited and CNOOC Southeast Asia Limited. Since October 2005, he became the executive vice president of CNOOC Limited and was primarily responsible for the offshore oilfield development and production of CNOOC Limited. Mr. Liu has been appointed as the Chief Executive Officer of the Company with effect from March 2009. In June 2009, Mr. Liu was appointed as Vice-Chairman of the

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APPENDIX PARTICULARS OF DIRECTORS PROPOSED TO BE RE-ELECTED


Company. In May 2010, Mr. Liu was appointed as Deputy General Manager of CNOOC. He was also appointed as Chairman of the Company and Offshore Oil Engineering Co., Ltd in August and December 2010 respectively.
There is no director service contract between the Company and Mr. Liu. Mr. Liu will not receive any director fee and his term of directorship is subject to retirement by rotation and re-election at the annual general meeting of the Company in accordance with the Articles.
- 7 -

SUPPLEMENTAL NOTICE OF ANNUAL GENERAL MEETING



(Incorporated in the People's Republic of China as a joint stock limited liability company)

(Stock Code: 2883) SUPPLEMENTAL NOTICE OF ANNUAL GENERAL MEETING

Reference is made to the notice (the "Initial Notice") of annual general meeting ("AGM") dated 17 April 2015, by which the AGM of China Oilfield Services Limited (the "Company") will be held at Room 504, CNOOC Plaza, 25 Chaoyangmen North Avenue, Dongcheng District, Beijing, the PRC, at 10.00 a.m. on Tuesday, 2 June 2015. This supplemental notice shall be read together with the Initial Notice.

THIS SUPPLEMENTAL NOTICE IS HEREBY GIVEN that the following proposed resolution will be considered and, if thought fit, approved by shareholders of the Company at the AGM as ordinary resolutions, in addition to the proposed resolutions set out in the Initial Notice:

(1) To re-elect Mr. Li Yong as an executive director of the Company with immediate effect.
(2) To re-elect Mr. Liu Jian as a non-executive director of the Company with immediate effect.
21 May 2015

Notes:

Second Proxy Form

By Order of the Board of

China Oilfield Services Limited Yang Haijiang

Company Secretary

1. A member entitled to attend and vote at the AGM is entitled to appoint one or more proxies (whether they are members of the Company or not) to attend and vote on his/ her/its behalf at the meeting(s).
2. The instrument appointing a proxy must be in writing signed by the appointer or his attorney duly authorised in writing. For appointer who is a legal person, the instrument appointing proxy should be signed under its seal or signed by its director or an attorney duly authorised in writing. For the instrument appointing proxy signed by an authorised person, the power of attorney or other documents of authorization must be
- 8 -

SUPPLEMENTAL NOTICE OF ANNUAL GENERAL MEETING


notarised. To be valid, the notarised power of attorney or other documents of authorisation and the proxy form must be delivered to the Office of the Board of the Company not less than 24 hours before the time appointed for holding of the AGM.
3. Since the proxy form (the "First Proxy Form") sent together with the Initial Notice does not contain the proposed resolutions for the re-election of Directors set out in this supplemental notice, a new proxy form (the "Second Proxy Form") has been prepared and is sent together with the Company's circular of which this supplemental notice of AGM forms part.
4. Shareholders are requested to complete and return the Second Proxy Form in accordance with the instructions printed thereon to the registrar of H Shares of the Company, Computershare Hong Kong Investor Services Limited at 17M Floor, Hopewell Centre, 183 Queen's Road East, Wanchai, Hong Kong not less than 24 hours before the time appointed for the holding of the relevant meeting or any adjournment thereof (as the case may be).
5. A shareholder who has not yet lodged the First Proxy Form with the Company is requested to lodge the Second Proxy Form if he/she wishes to appoint proxies to attend the AGM on his/her behalf. In this case, the First Proxy Form should not be lodged with the Company.
6. A shareholder who has already lodged the First Proxy Form with the Company should note that:
(i) if no Second Proxy Form is lodged with the Company, the First Proxy Form will be treated as a valid proxy form lodged by him/her if correctly completed. The proxy so appointed by the shareholder will be entitled to vote at his/her discretion or to abstain from voting on any resolution properly put to the AGM, including the resolution for, among other matters, the proposed re-election of Directors of the Company, as set out in this supplemental notice of AGM.
(ii) if the Second Proxy Form is lodged with the Company 24 hours prior to the time appointed for holding the AGM (the "Closing Time"), the Second Proxy Form will revoke and supersede the First Proxy Form previously lodged by him/her. The Second Proxy Form will be treated as a valid proxy form lodged by the shareholder if correctly completed.
(iii) if the Second Proxy Form is lodged with the Company after the Closing Time, the Second Proxy Form will be invalid. However, it will revoke the First Proxy Form previously lodged by the shareholder, and any vote that may be cast by the purported proxy (whether appointed under the First Proxy Form or the Second Proxy Form) will not be counted in any poll which will be taken on a proposed resolution. Accordingly, shareholders are advised not to lodge the Second Proxy Form after the Closing Time. In such case, if such Shareholders wish to vote at the AGM, they will have to attend in person and vote at the AGM themselves.
- 9 -

SUPPLEMENTAL NOTICE OF ANNUAL GENERAL MEETING


7. Shareholders are reminded that completion and delivery of the First Proxy Form and/or the Second Proxy Form will not preclude shareholders from attending and voting in person at the AGM or at any adjourned meeting should they so wish.

General

8. Shareholders should refer to other notes in the Initial Notice in relation to the AGM.

As at the date hereof, the executive directors of the Company are Messrs. Li Yong and Li Feilong, the non-executive directors of the Company are Messrs. Liu Jian (Chairman) and Zeng Quan and the independent non-executive directors of the Company are Messrs. Tsui Yiu Wa, Fong Wo, Felix and Law Hong Ping, Lawrence.

- 10 -

distributed by