- Octogon Man -- Odair Zanella
- Odal -- Odd Nordstoga
- Odd Nosdam -- Oddvar Hansen
- Oddvar Nygaards Kvartett -- Odes Of Ecstacy
- Odesii -- Odilon Martinez Quiroga
- Odin -- O.D.s
- O.D.'s -- O.E.M.
- Oen Bearen -- Of Word & Rhythm
- Ofag -- Off Planet Band
- Off Pop -- Officer Down
- Officer Flossie -- Offramp
- Offset -- OFWB
- OFX -- Ogabi
- Ogala Sioux Singers -- Ogün Sanlisoy
- 小倉優子 -- Oh No Joe
- Oh No Not Stereo -- OHCA
- OhD a.k.a. Mugz -- Ohmega Watts