The Williams River is a tributary of the Gauley River, 33 miles (53 km) long, in east-central West Virginia, USA. Via the Gauley, Kanawha and Ohio Rivers, it is part of the watershed of the Mississippi River, draining an area of 132 square miles (342 km²) in a sparsely populated region of the southern Allegheny Mountains and the unglaciated portion of the Allegheny Plateau.