For the Bois Blanc Island commonly called Boblo Island see Bois Blanc Island (Ontario)

Bois Blanc Island is coterminous with Bois Blanc Township, Mackinac County in the U.S. state of Michigan. The island is about 12 miles (19 km) long, 4 miles (6.4 km) wide in Lake Huron southwest of Mackinac Island and almost due north of the city of Cheboygan. The community of Pointe Aux Pins is on the south side and has ferry service to Cheboygan. In winter a safe path over the ice is marked by discarded Christmas trees allowing islanders to drive over to the mainland.

Islands of Michigan