| Uarini River | |
| Pushpin Map: | Brazil |
| River System: | Solimões River |
| Source1 Location: | Amazonas state |
| Mouth Location: | Uarini, Amazonas |
| Mouth Coordinates: | -2.9819°N -65.1101°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Brazil |
| Tributaries Right: | Copacá River |
The Uarini River (Portuguese: Rio Uarini) is a river of Amazonas state in north-western Brazil.It is a tributary of the Solimões River.
The Uarini River flows north through the Baixo Juruá Extractive Reserve, created in 2001.It then flows in a roughly northeast direction, entering the Solimões near the town of Uarini.