The Açuã River () is a river of Amazonas state in north-western Brazil, a tributary of the Mucuim River.
The river flows through the Mapinguari National Park, a conservation unit created in 2008. To the north of the national park it is crossed by the Trans-Amazonian Highway (BR-230), then runs through the Balata-Tufari National Forest, where it joins the Mucuim.
See also List of rivers of Amazonas
References
Brazilian Ministry of Transport