Oshima subprefecture (渡島) is located in Hokkaido, Japan.
Cities Hakodate (capital) Districts Kameda Kamedagun Ono Nanae Toi Esan Todohokke Kayabe Kayabegun Minamikayabe Shikabe Sawara Mori Yamakoshi Yamakoshigun Yakumo Oshamanbe Matsumae Matsumae Fukushima Kamiiso Kamiisogun Shiriuchi Kikonai Kamiiso