Aripuanã River is a river in Amazonas and Mato Grosso states in north-western Brazil. It is a tributary of the Madeira River in the Amazon Basin. The town of Novo Aripuanã is located on its banks where it merges into the Madeira River. The town of Aripuanã is also on its banks, but on the upper (southern) section of the river. The Trans-Amazonian highway crosses the Aripuanã.