Exhibit 15.10

TBPE REGISTERED ENGINEERING FIRM F-1580		FAX (713) 651-0849
1100 LOUISIANA    SUITE 4600	HOUSTON, TEXAS 77002-5294	TELEPHONE (713) 651-9191

Consent of Independent Consultant

We consent to the reference to our firm in the form and context in which they appear in this Annual Report on Form 20-F, and the inclusion of our reports herein for CNOOC Limited, and to the incorporation by the reference in any Registration Statement on Form F-3 and related Prospectus Supplements of CNOOC Limited for the registration of debt securities and guarantees previously filed with the Securities and Exchange Commission.

/s/ Ryder Scott Company, L.P.

RYDER SCOTT COMPANY, L.P.

TBPE Firm Registration No. F-1580

Houston, Texas

March 15, 2019

SUITE  800,  350  7TH  AVENUE, S.W.	CALGARY, ALBERTA T2P 3N9	TEL (403) 262-2799	FAX (403) 262-2790
621  17TH STREET, SUITE 1550	DENVER, COLORADO 80293-1501	TEL (303) 623-9147	FAX (303) 623-4258