J-POP Idol Series Beginning with O
- [Oshi no ko]
- Odd Taxi
- Odoru Daisosasen Series
- Oh-oku ( Danjo Gyakuten)
- Oh-oku / Ooku
- Ohitori sama
- Ohoka Echizen
- Oishinbo
- Ojamajo
- Okaeri Mone
- Okitegami Kyoko Series
- Okoshiyasu Chitose Chan
- Okusama wa Toriatsukaichui
- Olympic
- Omo ni Naiteimasu
- Omoi, Omoware, Furi, Furare
- Omoide no Marnie (When Marnie Was There)
- One Piece
- Onegai My Melody
- Ongaku to Hito
- Ongaku-shi ga Kakanai Jpop Hihyo
- Online Game
- Opanchu Usagi
- orange
- Orange Page
- Ore no Hanashi wa Nagai
- Ori Sta
- Orient
- Orthros no Inu
- Osama Game
- Osomatsu-san
- Osozaki no Himawari
- Ossan's Love
- Otenki One-san
- Otome continue
- otona MUSE
- Ouran Koko Host Club
- Ouroboros