- Oxana
- Ola Svensson
- Orquesta Típica Select
- Olti Al
- Orchestre à cordes de la Garde Républicaine
- Off Bloom
- Outline in Color
- 欧欧
- Octave
- Orchestra of the Americas
- Oleg Marshev
- Oryx
- OSI
- Oppermann
- Omega Drive
- Observer Drift
- Obie Bermudez (奥比·伯姆德兹)
- Odiseo
- Os Bons
- Orchestre de l'Opera National de Lyon
- Omaya
- Of You E.P.
- Our Time
- Opera Belles
- Onetox
- Opaz
- Os Apolos
- 欧阳江岸
- Orquesta Basura
- Orchestra Seattle
- Omfo
- Orlando Quartet (奥兰多弦乐四重奏)
- Oscar And The Wolf
- Olivs
- Oliver Pocher
- Ostrobothnian Chamber Orchestra
- Ola
- Octiv
- Otto Von Schirach
- Ozgur Ozkan
- Oskorri
- OD
- One Flew South
- Orphan Train
- Oscar De Leon
- Oh No! Yoko
- One Thousand
- On Air
- Oysterband
- 오지 (OZ)
- Orquestra de Câmara Brasileira
- Oh Boy
- OK걸스 (OK GIRLS)
- Overmono
- Orchestra Bagutti
- Ossie Scott
- Oh Yeah Band
- Osvaldo Requena y Leopoldo Federico
- Oranssi Pazuzu
- Osoyi Rizumu
