Umashima, Shimane

 is a volcanic island in the Sea of Japan, 2 km from the coast of the Shimane prefecture in Japan, just off the port Hamada, Shimane Prefecture. Umashima takes its name, meaning "Horse Island" from the fact what it was once used to be a grazing ground for horses.
While the island is uninhabited, it is actively used for swimming, fishing, rabbit watching and camping. It is administered as part of the Hamada Kaigan Prefectural Natural Park. The island features Shinto shrine. The lighthouse built in 1898 is visible up to . The scheduled ferry service from Hamada is available.