The Abuna River (, ) is a river in South America. As a part of the Amazon Basin, it forms part of the border between northern Bolivia and north-western Brazil. The river has a total length of . It originates in several streams east of the Cordillera Oriental of the Peruvian Andes. The river is navigable for circa in its lower northeastern part. At Manoa it joins the Río Madeira, a tributary of the Amazon. Opposite the river mouth there is the town of Abunã on the Brazilian side of the confluence. References Rivers of Acre (state) Rivers of Rondônia Bolivia–Brazil border International rivers of South America Rivers of Pando Department Border rivers