| East Branch Sebasticook River | |
| Mouth Location: | Sebasticook River |
| Mouth Coordinates: | 44.7606°N -69.3359°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Length Mi: | 26.7 |
The East Branch Sebasticook River is a tributary of the Sebasticook River in central Maine in the United States. It is part of the Kennebec River watershed.From the outflow of Lake Wassookeag (45.027°N -69.2887°W) in Dexter, the river runs about 12.7miles[1] south to Sebasticook Lake. From the outflow of the lake (44.8398°N -69.276°W) in Newport, the river runs about 9.5miles[1] southwest to its confluence with the Sebasticook in Detroit.