| Koko River | |
| Mouth Coordinates: | -1.9915°N 29.355°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Rwanda |
| Subdivision Type2: | District |
| Subdivision Name2: | Rutsiro District |
| River System: | Lake Kivu |
| Tributaries Left: | Rwishwa River |
The Koko River is a river in the Rutsiro District of western Rwanda that flows into Lake Kivu.
It is one of the main rivers draining the western Rwandan mountains into Lake Kivu, the other being the Sebeya River.During the colonial era the river defined the boundary between the Kibuye and Gisenyi Prefectures.The settlements of Gasiza and Murunda are close to the Koko's convergence with the Rwishwa River.