It is known only from three islands of the Ryukyu Archipelago, south of Japan, Okinawa (where the Yanbaru forest is situated), Amami Ōshima, and Tokunoshima.

[3] It is closely related to the frosted myotis, which is found on mainland Japan.

[2] It is only found in the fragments of mature forest remaining on Okinawa Island, Tokunoshima, and Amami Ōshima.

On Okinawa Island, it is found on United States military property.

It is listed as critically endangered because it only occurs on three islands, its extent of occurrence is less than 100 km2 (39 sq mi), and its habitat size and quality is being lost.