- Orquesta Broadway
- Otis
- Original Dixieland Jazz Band
- Orchestre Du Theatre National De L'opera-comique
- Owls
- Otis Murphy
- Oslo Gospel Choir
- Orplid
- Om
- Ozay Gönlüm
- Original Latin All Stars
- Oliver Fox
- 올빼미밴드 (Owl Band)
- Olexa Kabanov
- Otto Hype
- OOIOO
- Orchestra Cinema Paradise
- Outerspace
- Only Men Aloud
- Orange and Lemons
- Oregon
- Oesch's die Dritten
- OJS48
- Otto Winter
- Orquesta Real de Xalapa
- Orden der Wandalen
- Oliver Von Essen
- Old Man Gloom
- 온리 (Only)
- Olleo
- Of Norway
- 아웃오브캠퍼스 (Out Of Campus)
- Old Love Song Players
- Owen Sands
- Oscitone
- Osian Ellis
- Osvaldo Piro y su Orquesta
- Octavius
- One Dae
- Oztronix Band
- Orquesta Típica Francisco Canaro
- Overloque
- Olde Worlde (Sohhei Numata)
- Olga Kern
- Oasis Worship
- Olaf Hund
- Owl
- Over Range
- Ortzy
- ONNGAKUCENTER KARAOKE
- Ocean Grove
- Ovall
- Oy
- Omega One
- Orquesta y Coros Jóvenes Europeos
- Oz Romita
- One-Way Mirror
- Olle Ljungström
- Outrage
- Overtune
