O – List All Anime
All anime series and cartoons begins with the letter "O". The comments, description of Anime.
- Oban Star-Racers
- Occult Academy
- Occultic;Nine
- Ocean Waves
- Oda Nobuna No Yabou
- Oh! Edo Rocket
- Ojisan to Marshmallow
- Okusama ga Seitokaichou!
- Omamori Himari
- Omoi no Kakera
- Omoide no Marnie
- Onara Gorou
- One Off
- One Outs
- One Piece
- One Punch Man
- One Room
- One Stormy Night Movie
- Onee-chan ga Kita
- Onegai Teacher
- Onegai Twins
- Ongaku Shoujo
- OniAi
- Onigiri
- Onihei
- Onii-chan
- Only Yesterday
- Onmyou Taisenki
- Onsen Yousei Hakone-chan
- Ookami Kakushi
- Ookami Kodomo no Ame to Yuki
- Ookami Shoujo to Kuro Ouji
- Ookami-san to Shichinin no Nakama-tachi
- Ookiku Furikabutte
- Ooya-san wa Shishunki!
- Orange
- Ore ga Ojousama Gakkou ni "Shomin Sample" Toshite Gets♥Sareta Ken
- Ore Monogatari!!
- Ore no Nounai Sentakushi ga, Gakuen Love Comedy wo Zenryoku de Jama Shiteiru
- Ore-sama Kingdom
- Ore-tachi ni Tsubasa wa Nai
- Ore, Twintails ni Narimasu.
- Oreca Battle
- Oregairu
- Oreimo
- Orenchi no Furo Jijou
- OreShura
- Origin: Spirits of the Past
- Osamu Tezuka`s Buddha
- Oseam
- Oshiete! Galko-chan
- Osomatsu-san
- Otome wa Boku ni Koishiteru
- Otome Youkai Zakuro
- Ouran High School Host Club
- Oushitsu Kyoushi Haine
- Outbreak Company
- Outlaw Star
- Over Drive
- Overlord
- Owari no Seraph
- Owarimonogatari
- Oyayubi Hime Monogatari
- Ozmafia!!
- Ozuma