CNOOC : APPOINTMENT OF THE VICE CHAIRMAN

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(Incorporated in Hong Kong with limited liability under the Companies Ordinance)

(Stock Code: 00883)

APPOINTMENT OF THE VICE CHAIRMAN

The Board is pleased to announce that Mr. Wang Dongjin, a Non-executive Director of the

Company, has been appointed as the Vice Chairman of the Company with effect from 5

December 2018.

The board of directors(the "Board") of CNOOC Limited (the "Company") is pleased toannounce that Mr. Wang Dongjin("Mr. Wang"), a Non-executive Director of the Company, has been appointed as the Vice Chairman of the Company with effect from 5 December 2018.

Wang Dongjin

Born in 1962, Mr. Wang is a professor-level senior engineer and received a Bachelor of Science degree in Petroleum Drilling from Development Department of China University of Petroleum and a Doctor of Science degree in Petroleum Engineering Management from China University of Petroleum-Beijing in 2012. From July 1995 to December 1997, he was appointed as Deputy Director-General of Jiangsu Petroleum Exploration Bureau. From December 1997 to October 2002, he was appointed as Vice President of China National Oil & Gas Exploration and DevelopmentCorporation ("CNODC"). From December 2000 to October 2002, he also served as President ofCNPC International (Kazakhstan) Ltd. and President of Aktobe Munai Gas Corp. From October 2002 to September 2008, he served as President of CNODC. From January 2004 to September2008, he was appointed as Assistant President of China National Petroleum Corporation ("CNPC")and Vice Chairman of CNODC. From September 2008 to March 2018, he served as Vice President of CNPC. From May 2011 to May 2014, he was concurrently appointed as Director of PetroChinaCompany Limited ("PetroChina"). From July 2013 to March 2018, he was concurrently appointedas President of PetroChina. From May 2014 to March 2018, he served as Vice Chairman of PetroChina. In March 2018, Mr. Wang was appointed as a Director of China National Offshore Oil Corporation("CNOOC"). In October 2018, Mr. Wang was appointed as President of CNOOC. On 27 April 2018, Mr. Wang was appointed as a Non-executive Director and a member of the

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Remuneration Committee of the Company. Mr. Wang has been appointed as the Vice Chairman of the Company with effect from 5 December 2018.

The Company and Mr. Wang have entered into a service agreement on 27 April 2018. Pursuant to the service agreement between the Company and Mr. Wang, the Company does not pay him anydirector's fee. The Remuneration Committee of the Company will review the level of directors'emolument and make recommendation to the Board for adjustments if necessary. Mr. Wang'sappointment continued for a period of twelve months and would be renewed annually asdetermined by the Board or the shareholders of the Company, subject to three months' notice oftermination by either party.

As at the date of this announcement and save as disclosed above, Mr. Wang has not held any other directorship in any listed public companies in the past three years and does not have any interest in the shares of the Company within the meaning of the Securities and Futures Ordinance (Chapter 571 of the Laws of Hong Kong).

Save as disclosed above, Mr. Wang does not have any relationship with any director, senior management, substantial shareholder or controlling shareholder of the Company.

Save as disclosed above, there is no other information required to be disclosed pursuant to the requirements of Rules 13.51(2)(h) to 13.51(2)(v) of the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited, nor are there any other matters that need to be brought to the attention of the shareholders of the Company.

The Board would like to take this opportunity to offer Mr. Wang its sincere congratulations on his appointment as the Vice Chairman of the Company.

By Order of the Board

CNOOC Limited

Wu XiaonanJoint Company Secretary

Hong Kong, 5 December 2018

As at the date of this announcement, the Board comprises the following:

Executive Directors	Independent Non-executive Directors
Yuan Guangyu	Chiu Sung Hong
Xu Keqiang	Lawrence J. Lau
Tse Hau Yin, Aloysius
Non-executive Directors	Kevin G. Lynch
Yang Hua(Chairman)
Wang Dongjin(Vice Chairman)
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