Isle Royale Queen IV is a passenger ferry operating on Lake Superior between Copper Harbor, Michigan, and Isle Royale National Park, the largest island on Lake Superior and the State of Michigan's only national park.

The Queen IV makes this crossing in three hours, fifteen minutes, depending on weather conditions on Lake Superior.

The ferry began operations on the run in 2005 after being purchased by the family in Port Canaveral, Florida, in 2004.

The ferry was built in 1980 in Louisiana, but operated for many years as a tour boat named the John Jay in New York's lower harbor.

In late July 2015, the vessel ran aground, and the Ranger III was called upon to bring the Isle Royale Queen IV's passenger back to the mainland.