| Arapiuns River | |
| Source1 Location: | Pará state |
| Subdivision Type1: | Country |
The Arapiuns River is a river in Pará state in north-central Brazil, which It is a tributary of the Tapajós, and merges into the latter river about 30km (20miles) before Tapajós merges into the Amazon River. Arapiuns is a blackwater river.