| Gurupi River | |
| Pushpin Map: | Brazil |
| Source1 Location: | Maranhão state |
| Source2 Location: | Pará state |
| Mouth Location: | Atlantic ocean |
| Mouth Coordinates: | -1.1168°N -46.055°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Brazil |
The Gurupi River is a river in north-central Brazil that forms the boundary between Maranhão and Pará states. The Gurupi rises in the low hills that separate its basin from that of the Tocantins River to the south, and flows north into the Atlantic Ocean. The Serra do Tiracambu lies to the east, and separates the basin of the Gurupi from that of the Pindaré River.
Part of the basin lies in the Gurupi Biological Reserve, a fully protected conservation unit created in 1988. The average annual rainfall is .Temperatures range from 22to with an average of .The Gurupi basin is home to tropical moist broadleaf forest, and lies within the Tocantins–Araguaia–Maranhão moist forest ecoregion.