(Hong Kong, May 19, 2015) - The Board of Directors ("the Board") of CNOOC Limited (the “Company”, NYSE: CEO, SEHK: 00883, TSX: CNU) announced today that Mr. Wang Yilin has resigned from his positions as Chairman of the Board, Chairman of the Nomination Committee and Non-executive Director of the Company. Mr. Yang Hua, an existing Non-executive Director of the Company, has been appointed as Chairman of the Board and Chairman of the Nomination Committee of the Company. In addition, Mr. Yang has no longer served as Vice-chairman of the Board. The aforementioned changes become effective from today.

Yang Hua
Born in 1961, Mr. Yang is a professor-level senior engineer and graduated from China University of Petroleum with a B.S. degree in petroleum engineering. He also received an MBA degree from the Sloan School of Management at MIT as a Sloan Fellow. Mr. Yang joined CNOOC in 1982 and has over 30 years of experience in petroleum exploration and production. From 1982 to 1992, Mr. Yang served in a number of positions in CNOOC Research Center including the Director of Field Development Department, the Manager of Reservoir Engineering Department and the Project Manager. Thereafter, Mr. Yang was mainly involved in international business, M&A, corporate finance and capital market operations in the Company and its subsidiaries. From 1993 to 1999, he served as the Deputy Chief Geologist, the Deputy Director and the Acting Director for Overseas Development Department of the Company and the Vice President of CNOOC International Limited, a subsidiary of the Company. From 1999 to 2011, Mr. Yang served in a number of positions in the Company including Senior Vice President, Chief Financial Officer, Executive Vice President, President and Chief Executive Officer. Mr. Yang also served as an Assistant President of CNOOC from November 2006 to April 2010 and as Vice President of CNOOC from April 2010 to August 2011. Mr. Yang served as Director and President of CNOOC from August 2011 to April 2015. He was appointed as Chairman of CNOOC in April 2015. In addition, he serves as Chairman and Director of CNOOC China Limited and CNOOC International Limited, both being subsidiaries of the Company. He also served as Director and President of CNOOC Southeast Asia Limited, General Manager of CNOOC China Limited, Chairman and Director of CNOOC Southeast Asia Limited and Chairman and Director of CNOOC Deepwater Development Limited, all being subsidiaries of the Company. He also served as Director of CNOOC Finance Corporation Limited, a subsidiary of CNOOC. Mr. Yang was appointed as an Executive Director of the Company with effect from 31 August 2005 and was the Vice Chairman of the Board of the Company from 16 September 2010 to 19 May 2015, and was re-designated from an Executive Director to a Non- Executive Director of the Company with effect from 23 November 2011.  Mr. Yang has been appointed as Chairman of the Board and Chairman of the Nomination Committee of the Company with effect from 19 May 2015.

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Notes to Editors:

More information about the Company is available at http://www.cnoocltd.com

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This press release includes “forward-looking statements” within the meaning of the United States Private Securities Litigation Reform Act of 1995, including statements regarding expected future events, business prospectus or financial results. The words “expect”, “anticipate”, “continue”, “estimate”, “objective”, “ongoing”, “may”, “will”, “project”, “should”, “believe”, “plans”, “intends” and similar expressions are intended to identify such forward-looking statements. These statements are based on assumptions and analyses made by the Company in light of its experience and its perception of historical trends, current conditions and expected future developments, as well as other factors the Company believes are appropriate under the circumstances. However, whether actual results and developments will meet the expectations and predictions of the Company depends on a number of risks and uncertainties which could cause the actual results, performance and financial condition to differ materially from the Company’s expectations, including but not limited to those associated with fluctuations in crude oil and natural gas prices, the exploration or development activities, the capital expenditure requirements, the business strategy, whether the transactions entered into by the Group can complete on schedule pursuant to their terms and timetable or at all, the highly competitive nature of the oil and natural gas industries, the foreign operations, environmental liabilities and compliance requirements, and economic and political conditions in the People’s Republic of China. For a description of these and other risks and uncertainties, please see the documents the Company files from time to time with the United States Securities and Exchange Commission, including the 2014 Annual Report on Form 20-F filed on 22 April 2015.

Consequently, all of the forward-looking statements made in this press release are qualified by these cautionary statements. The Company cannot assure that the results or developments anticipated will be realised or, even if substantially realised, that they will have the expected effect on the Company, its business or operations.

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