SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16 OF THE

SECURITIES EXCHANGE ACT OF 1934

December 2009

Commission File Number: 333-153452

ECOPETROL S.A.

(Exact name of registrant as specified in its Charter)

Carrera 7 No. 37 – 69

BOGOTA – COLOMBIA

(Address of registrant’s principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F x Form 40-F o

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):

Yes        o No x

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):

Yes        o No x

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        o No x

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b):  82-    N/A   

PRESS RELEASE

Ecopetrol S.A. Modifies its Corporate Governance Code

BOGOTA, Ecopetrol S.A. (NYSE: EC; BVC: ECOPETROL; BVL: EC) (“Ecopetrol” or the “Company”) reports to its shareholders and the general public that, on December 11, 2009, the Company’s Board of Directors approved several modifications to the Company's Corporate Governance Code (“Code”).

The primary changes are as follows:

· Board of Directors Committees: The Business Committee is now a permanent committee of the Board of Directors.

· Corporate Social Responsibility (Responsabilidad Social Empresarial (RSE)): The RSE sections of the Code have been revised to reflect the Company’s new strategy with respect to its shareholders and the commitments made to them within the realm of corporate social responsibility.

· External controls: The Code now makes note of the concurrent oversight of Ecopetrol exercised by the Superintendency of Ports and Transportation and the Superintendency of Health.

· Office of Disciplinary Control (Oficina de Control Disciplinario (OCD)): The Code has been modified in order to clarify that Ecopetrol's OCD will continue to oversee disciplinary investigation proceedings.

The complete text of the Code can be found on the Company’s website at www.ecopetrol.com.co.

Bogotá, Colombia, December 15, 2009

------------------------------------------

Ecopetrol is Colombia’s largest integrated oil company and is among the top 40 oil companies in the world and the four largest oil companies in Latin America. Besides Colombia, where it accounts for 60% of total production, the Company is involved in exploration and production activities in Brazil, Peru and the United States (Gulf of Mexico). Ecopetrol has the principal refinery in Colombia, most of the network of oil and multiple purpose pipelines in the country, and it is considerably increasing its participation in biofuels.

 Dirección de Relacionamiento con el Inversionista Tel: 2345190 – Fax: 2345648    investors@ecopetrol.com.co

www.ecopetrol.com.co

PRESS RELEASE

This release contains forward-looking statements relating to the prospects of the business, estimates for operating and financial results, and those related to growth prospects of Ecopetrol. These are merely projections and, as such, are based exclusively on the expectations of management concerning the future of the business and its continued access to capital to fund the Company’s business plan. Such forward-looking statements depend, substantially, on changes in market conditions, government regulations, competitive pressures, the performance of the Colombian economy and the industry, among other factors; therefore, they are subject to change without prior notice.

Contact us for any additional information:

Investor Relations

Alejandro Giraldo

Phone: +571-234-5190

Email: investors@ecopetrol.com.co

Media Relations (Colombia)

Mauricio Téllez

Phone: + 571-2345377

Fax: +571-2344480

Email: mtellez@ecopetrol.com.co

Website: www.ecopetrol.com.co

 

 Dirección de Relacionamiento con el Inversionista Tel: 2345190 – Fax: 2345648    investors@ecopetrol.com.co

www.ecopetrol.com.co

SIGNATURE

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, thereto duly authorized.

Date:  December 15, 2009

Ecopetrol S.A.
By:	/s/ Adriana M. Echeverri
Name:	Adriana M. Echeverri
Title:	Chief Financial Officer