Washington, D.C. 20549
Report of Foreign Private Issuer
Pursuant to Rule 13a-16 or 15d-16
of the Securities Exchange Act of 1934

For the month of March 2015

Commission File Number 1-14966
CNOOC Limited
(Translation of registrant’s name into English)
65th Floor
Bank of China Tower
One Garden Road
Central, Hong Kong
(Address of principal executive offices)
Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F       X             Form 40-F ___

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ____

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ____

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.
Yes   ___         No     X    

If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b):  Not applicable


Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

CNOOC Limited
/s/ Hua Zhong
Hua Zhong
Joint Company Secretary

Dated: March 13, 2015


Exhibit No.
Exhibit 99.1
Announcement dated March 13, 2015, entitled DATE OF BOARD MEETING.

Exhibit 99.1
Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this announcement, 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 announcement.

(Incorporated in Hong Kong with limited liability under the Companies Ordinance)
(Stock Code: 00883)

The board of directors (the "Board") of CNOOC Limited (the "Company") announces that a meeting of the Board will be held on Friday, 27 March 2015, whereat the Board will, amongst other matters, approve the annual results of the Company and its subsidiaries for the year ended 31 December 2014 and consider the recommendation on payment of a final dividend.
By Order of the Board
CNOOC Limited
Zhong Hua
Joint Company Secretary

Hong Kong, 13 March 2015

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

Executive Directors
Li Fanrong
Wu Guangqi
Non-executive Directors
Wang Yilin (Chairman)
Yang Hua (Vice Chairman)
Lv Bo
Wang Jiaxiang
Independent Non-executive Directors
Chiu Sung Hong
Lawrence J. Lau
Tse Hau Yin, Aloysius
 Kevin G. Lynch