| Yí River | |
| Source1 Location: | Cuchilla Grande highlands |
| Mouth Location: | Río Negro (Uruguay) |
| Subdivision Type1: | Country |
| Subdivision Name1: | Uruguay |
| Length: | 210km (130miles) |
The Yí River (Spanish, Río Yí) is a river in Uruguay. The Yí and the Tacuarembó Rivers are the principal tributaries of the Río Negro.
The Yí River originates in the Cuchilla Grande highlands. It flows generally west through central Uruguay to the Río Negro.
Various other rivers, including the Porongos River and Chamangá River, are tributaries of the Yí River.
The Yí forms much of the boundary between Durazno Department and Florida Department.
Subsequently, it forms part of the boundary between Durazno Department and Flores Department, where the Chamangá River its tributary.