Onion River may refer to a waterway in the United States:
Onion River (Minnesota) Onion River, a tributary of the St. Regis River in New York Onion River (Sheboygan River), a tributary of the Sheboygan River in Wisconsin Onion River, a tributary of Lake Superior in Wisconsin
See also Winooski River in Vermont, from the Abenaki word for "onion"