Exhibit 8.1

Subsidiaries of Ecopetrol S.A.

The following table sets forth our subsidiaries, their respective countries of incorporation, our percentage ownership in each (both directly and indirectly through other subsidiaries) at March 31, 2017.

COMPANY	COUNTRY OF  INCORPORATION	OWNERSHIP
ANDEAN CHEMICALS LIMITED	Bermuda		100.00	%
BLACK GOLD RE LIMITED	Bermuda		100.00	%
CENIT TRANSPORTE Y LOGÍSTICA DE HIDROCARBUROS S.A.S.	Colombia		100.00	%
ECOPETROL CAPITAL AG	Switzerland		100.00	%
ECOPETROL GLOBAL ENERGY S.L.U	Spain		100.00	%
ECOPETROL GLOBAL CAPITAL S.L.U.	Spain		100.00	%
EQUION ENERGÍA LIMITED	United Kingdom		51.00	%
HOCOL PETROLEUM LIMITED	Bermuda		100.00	%
BIOENERGY S.A.**	Colombia		98.61	%
BIOENERGY ZONA FRANCA S.A.S.**	Colombia		98.61	%
COLOMBIA PIPELINES LIMITED**	United Kingdom		51.00	%
COMPOUNDING AND MASTERBATCHING INDUSTRY LTDA - COMAI**	Colombia		100.00	%
ECOPETROL AMERICA INC**	United States		100.00	%
ECOPETROL DEL PERU S.A.**	Peru		100.00	%
ECOPETROL OLEO & GAS DO BRASIL LTDA**	Brazil		100.00	%
ECP OIL AND GAS GERMANY GMBH**	Germany		100.00	%
HOCOL S.A.**	Cayman Islands		100.00	%
OLEODUCTO BICENTENARIO DE COLOMBIA S.A.S.**	Colombia		55.97	%
OLEODUCTO CENTRAL S.A. - OCENSA**	Colombia		72.65	%
OLEODUCTO DE COLOMBIA S.A. - ODC**	Colombia		73.00	%
OLEODUCTO DE LOS LLANOS  ORIENTALES  S.A.**	Panama		65.00	%
REFINERIA DE CARTAGENA S.A. *	Colombia		100.00	%
PROPILCO S.A.*	Colombia		100.00	%
SANTIAGO OIL COMPANY**	Cayman Islands		51.00	%
ESENTTIA RESINAS DEL PERU SAC**	Peru		100.00	%
ECOPETROL COSTA AFUERA COLOMBIA S.A.S**	Colombia		100.00	%

*Direct and indirect participation.
**Solely indirect participation through other subsidiaries or affiliates.