| Acomayo River | |
| Name Etymology: | Quechua |
| Pushpin Map Caption: | Location of the mouth in Peru |
| Subdivision Type1: | Country |
| Subdivision Name1: | Peru |
| Subdivision Type3: | Region |
| Subdivision Name3: | Huánuco Region |
| Mouth: | Huallaga River |
| Mouth Coordinates: | -9.8212°N -76.0603°W |
Acomayo River (possibly from Quechua aqu sand, mayu river,[1] "sand river") is a river in Peru located in the Huánuco Region, Huánuco Province, Chinchao District. It is a left tributary of the Huallaga River. The confluence is southeast of the town Acomayo, near the village Tingo Pampa.