Exhibit 23.5
Consent of DeGolyer and MacNaughton
DeGolyer and MacNaughton
5001 Spring Valley Road
Suite 800 East
Dallas, Texas 75244
July 26, 2013
Board of Directors
Ecopetrol S.A
Calle 35 No. 7-21 Piso 1
Bogota, D.C. Colombia
Ladies and Gentlemen:
We hereby consent to the references to DeGolyer and MacNaughton, as set forth in the Ecopetrol S.A Registration Statement on Form F-3, filed with the United States Securities and Exchange Commission on July 26, 2013, under the heading "Experts" and to the incorporation by reference of the other references to our firm and information derived from our third party letter report dated February 26, 2013 (our Report) contained in the Annual Report of Ecopetrol S.A on Form 20-F for the year ended December 31, 2012.
Our Report referenced above consists of evaluations of Ecopetrol S.A's interests and reserves in certain areas in Colombia and Peru for the fiscal year ending December 31, 2012.
Very truly yours,
DeGOLYER and MacNAUGHTON
Texas Registered Engineering Firm F-716