Atsumi Peninsula

 is a peninsula in southern Aichi Prefecture, central Honshū, Japan. It has an approximate length of east-west, separating Mikawa Bay (to the north) from the Philippine Sea to the south, with Ise Bay lying to its west. It faces the Chita Peninsula, to the northwest, across the entrance to Mikawa Bay. It has a width ranging from to , and its highest point is . Its total area is approximately 200 square kilometers.
Atsumi Peninsula is noted for its temperate climate, due to the warm Kuroshio Current offshore. The rock formations at Cape Irago, its western tip, and its beaches are part of the Mikawa Wan Quasi-National Park. Administratively, almost all of the peninsula falls within the city of Tahara, with its eastern "neck" within the city of Toyohashi.