| Preto River | |
| Pushpin Map: | Brazil |
| River System: | Rio Grande |
| Source1 Location: | Bahia state |
| Mouth: | Rio Grande |
| Mouth Coordinates: | -11.3526°N -43.8373°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Brazil |
The Preto River, a tributary of the Rio Grande, is a river of Bahia state in eastern Brazil.
The river basin includes part of the Serra Geral do Tocantins Ecological Station, a strictly protected conservation unit created in 2001 to preserve an area of cerrado.