Ōshika is a village located in Nagano Prefecture, Japan. As of 1 October 2018, the village had an estimated population of 977, and a population density of 3.9 persons per km2. The total area of the village is 248.28 square kilometres (95.86 sq mi). Ōshika is listed as one of the Most Beautiful Villages in Japan.

Nagano Prefecture is a landlocked prefecture of Japan located in the Chūbu region of Honshū. Nagano Prefecture has a population of 2,007,682 and has a geographic area of 13,561.56 square kilometres (5,236.15 sq mi). Nagano Prefecture borders Niigata Prefecture to the north, Gunma Prefecture to the northeast, Saitama Prefecture to the east, Yamanashi Prefecture to the southeast, Shizuoka Prefecture and Aichi Prefecture to the south, and Gifu Prefecture and Toyama Prefecture to the west.