| COMPANY                                               |         | COUNTRY OFINCORPORATION |         | OWNERSHIP % |         | VOTING % |
|-------------------------------------------------------|--------------|------------------------------|--------------|------------------|--------------|---------------|
|                                                  |         |                         |         |             |         |          |
| Ecopetrol      Oleo e Gas do Brasil Ltda*             |         | Brazil                       |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Ecopetrol      del Perú S.A.*                    |         | Perú                    |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Ecopetrol      America Inc.*                          |         | United      States           |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Black      Gold Re                                    |         | Bermuda                      |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Andean      Chemicals Ltd.                            |         | Bermuda                      |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| ODL      Finance S.A.                                 |         | Panama                       |         | 65               |         | 65            |
|                                                  |         |                         |         |             |         |          |
| Propilco      S.A.*                                   |         | Colombia                     |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Bioenergy      S.A.**                                 |         | Colombia                     |         | 85               |         | 85            |
|                                                  |         |                         |         |             |         |          |
| Ecopetrol      Global Energy S.L.U.                   |         | Spain                        |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Ecopetrol      Pipelines International Ltd.**         |         | Bermuda                      |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Ecopetrol      Transportation Company                 |         | Cayman      Islands          |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Offshore      International Group Inc. – OIG(1) |         | United      States           |         | 50               |         | 50            |
|                                                  |         |                         |         |             |         |          |
| Savia      Perú S.A.**(1)                        |         | Perú                    |         | 50               |         | 50            |
|                                                  |         |                         |         |             |         |          |
| Ecodiesel      Colombia S.A.(1)                       |         | Colombia                     |         | 50               |         | 50            |
|                                                  |         |                         |         |             |         |          |
| Refinería      de Cartagena S.A.*                |         | Colombia                     |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Serviport      S.A.(1)                                |         | Colombia                     |         | 49               |         | 49            |
|                                                  |         |                         |         |             |         |          |
| Oleoducto      de Colombia S.A.*                      |         | Colombia                     |         | 65.57            |         | 65.57         |
|                                                  |         |                         |         |             |         |          |
| Oleoducto      Central S.A.*                          |         | Colombia                     |         | 60               |         | 60            |
|                                                  |         |                         |         |             |         |          |
| Hocol      Petroleum Limited                          |         | Bermuda                      |         | 100              |         | 100           |
|                                                  |         |                         |         |             |         |          |
| Invercolsa      S.A.(1)                               |    | Colombia                     |    | 31.76            |    | 31.76         |

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