The Kokosing River (ko-KO-sing) is a tributary of the Walhonding River, 57.2 miles (92.1 km) long, in east-central Ohio in the United States. Via the Walhonding, Muskingum and Ohio Rivers, it is part of the watershed of the Mississippi River, draining an area of 482 square miles (1248 km²).[1]