- O
- OO
- OO
- OOak
- OakOb
- ObeOBO
- ObrOce
- OceOch
- Och
- OctODE
- OdeODO
- odoOf
- OfOff
- OffOgr
- OgrOh
- OhaOis
- OisOka
- OkaOku
- OkuOlc
- OldOld
- OldOli
- OliOli
- OliOls
- OlsOma
- OmaOme
- OMFOn
- OnOne
- OneOne
- ONEOne
- oneOnk
- OnkOnT
- OntOor
- OorOpe
- OpeOpu
- OpuOra
- OraOrc
- OrcOrd
- OrdOrh
- OrhOri
- OriOrl
- OrlOrq
- OrqOrt
- OrtOsa
- OsaOsc
- OscOsm
- Osn
- Otr
- OtrOtt
- OttOur
- OurOut
- OutOut
- OutOve
- OveOve
- OveOwe
- OweOxi
- OxiOze
- ozz
- Orlons, The (US R&B group)
- Orlova, Alina
- Orlowski, Kris
- Orlowsky, David
- Orlowsky, David, Trio
- ORM (epic/melodic black metal band from Denmark)
- Ormai
- Ormandy, Eugene (conductor)
- Ormandy, Eugene & Philadelphia Orchestra, The
- Ormåsen, Gaute
- Ormaz (French rapper)
- Orme, Le
- Ormiston
- Ormonde
- Orna
- Ornament (Afghan Whigs and Marcy Mays)
- Ornaments (Italian band)
- Ornatos Violeta
- Orne
- Ornelas, Raúl
- Ornella Napolitani
- Ornery (Folk punk band from Vancouver, BC, Canada)
- Ornette (French‐Italian singer‐songwriter multi‐instrumentalist)
- Ornithology
- ORO (Uruguay)
- Oro Sólido
- Oro Swimming Hour
- Orochen (Post-rock / folk from Sweden)
- Orochi (Brazilian rapper)
- Orofino, Richard
- Orok, Shayne
- Öröm
- Oropesa, Omar (Christian music singer)
- Oros (Slovakian goregrind)
- Ôros Kaù (Belgian black metal)
- Oroza, Bobby
- Oroza, Bobby feat. Cold Diamond & Mink
- Orozco Barrientos
- Orozco, Alejandra
- Orozco, Antonio (Spanish singer-songwriter)
- Orozco, Antonio & KAROL G
- Orozco, Antonio feat. Fonsi, Luis
- Orozco, Antonio feat. Malú
- Orozco, José-Luis
- Orozco, Regina
- Orozco, Verónica
- Orphan (deathcore band)
- Orphan Boy
- Orphan Hate
- Orphan Newsboys, The
- Orphan Prodigy
- Orphan Project
- Orphan Songs
- Orphan Swords (Belgian duo)
- Orphan Zero
- Orphanage
- Orphaned Land
- Orphaned Land & Amaseffer
- Orphaned Land feat. Hackett, Steve
- Orphaned Land feat. Koray, Erkin
- Orphaned Land feat. Kürsch, Hansi
- Orphaned Land feat. Lindberg, Tomas
- Orphaned Land feat. Poliker, Yehuda
- Orphaned Land feat. Wilson, Steven
- orphantwin
- Orphax (Dutch ambient / drone musician)
- Orphean Passage
- Orphei Drängar
- Orphei Drängar, Sund, Robert
- Orpheus (Australian death metal band)
- Orpheus (60s/70s Boston rock band)
- Orpheus (masquerade drag artist)
- Orpheus Boys Choir (on 1974 Schonberg BBC cd & 1996 Christmas cd)
- Orpheus Chamber Orchestra (US orchestra)
- Orpheus Ensemble, The
- Orpheus Nine
- Orpheus Omega
- Orphies
- Orphx (Canadian industrial / techno project)
- ORPHY (Kirill Rogovets)
- Orplid
- Orquesta Akokán
- Orquesta América (Cuban charanga)
- Orquesta Aragón
- Orquesta Broadway
- Orquesta Bronko
- Orquesta Calibre (Columbian salsa orchestra)
- Orquesta Caliente
- Orquesta Canela
- Orquesta Cubana de Música Moderna