Walpole Island is an island in southwestern Ontario, Canada on the border between Ontario and Michigan in the United States. It is located in the mouth of the St. Clair River on Lake St. Clair, approximately thirty miles (50 km) northeast of Detroit, Michigan, and Windsor, Ontario. It is unceded territory and is inhabited by the Chippewa, Potawatomi, and Ottawa peoples. According to one tradition, Tecumseh's grave is on the reserve there. On most maps, the island is shown as included in Lambton County.

First Nations reserves in Ontario | Islands of Ontario | Great Lakes | Lambton County, Ontario