| Piraquê Açu River | |
| Pushpin Map: | Brazil |
| Source1 Location: | Espírito Santo state |
| Mouth Location: | Atlantic ocean |
| Mouth Coordinates: | -19.9515°N -40.1525°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Brazil |
The Piraquê Açu River is a river of Espírito Santo state in eastern Brazil.
Part of the river basin is contained in the Augusto Ruschi Biological Reserve, a fully protected area.