Japonsko - Zoznam miest na písmeno O
- Ōami
- Ōamishirasato
- Ōarai
- Obama
- Obanazawa
- Obihiro
- Obita
- Ōbu
- Oda
- Ōdachō-ōda
- Ōdate
- Odawara
- Ōfunato
- Oga
- Ōgaki
- Ogasawara
- Ogawa
- Ogi
- Ogōri
- Ogōri-shimogō
- Ōhara
- Ōi
- Ōiso
- Ōita
- Ojiya
- Ōkawa
- Ōkawara
- Okaya
- Okayama
- Okazaki
- Okegawa
- Okinawa
- Ōkuchi-shinohara
- Okunoya
- Ōmachi
- Omaezaki
- Ōmagari
- Ōmamachō-ōmama
- Ōme
- Omigawa
- Ōmihachiman
- Omitama
- Ōmiya
- Ōmura
- Ōmuta
- Onagawa Chō
- Ono
- Ōno-hara
- Onoda
- Ōnojō
- Onomichi
- Osaka
- Ōsaka-sayama
- Ōsaki
- Ōshima
- Ōshū
- Ōta
- Ōtake
- Otaru
- Ōtawara
- Otofuke
- Ōtsu
- Ōtsuchi
- Ōtsuki
- Ōuda
- Owase
- Oyabe
- Oyama
- Ōzu