- O
- OO
- OO
- OO
- OOaf
- OAFOaK
- OakOBE
- ObeObn
- OBO
- Oce
- OceOCS
- OCTOct
- OctOdd
- OddODE
- ODEOdo
- OdoOf
- OfOff
- OffOff
- OffOgr
- OgrOh
- ohOHM
- OHNOiz
- OizOka
- OkaOkl
- OklOla
- OlaOld
- OldOld
- OldOle
- OleOli
- OliOli
- OliOls
- OlsOm
- OMOma
- OmaOme
- OmeOMO
- OmoOna
- OnaOne
- ONEONE
- ONEOne
- OneONE
- ONEOnl
- OnlOns
- OnsOol
- OolOpe
- OpeOPF
- OpgOpt
- OptOra
- OraOrb
- OrbOrc
- Orcorc
- orcOre
- OreOrh
- OrhOri
- OriOrk
- OrkOrn
- OrnOrq
- OrqOrs
- OrsOrt
- OrtOsb
- OsbOsc
- OscOsl
- OslOst
- OstOte
- OteOTR
- OTROtt
- OttOud
- OueOur
- OurOut
- OUTOut
- OutOut
- OutOve
- OveOve
- OveOwe
- OweOwl
- OwlOxo
- Oxo
- OzOzu
- ozwozz
- Ornob
- ORO (Uruguay)
- Oro Negro (Grupo de Ecuador)
- Oro Sólido
- Oro Swimming Hour
- Oro y Plata, Dueto
- Orobians, The
- Orochen (Post-rock / folk from Sweden)
- Orochi (Brazilian rapper)
- Orodruin (Traditional Doom Metal band from U.S.A.)
- Orofino, Richard
- Orok, Shayne
- Orok, Shayne & Orok, Ali
- Öröm
- Oronti
- Oropesa, Omar (Christian music singer)
- Ôros Kaù (Belgian black metal)
- Orouni
- Oroza, Bobby
- Oroza, Bobby & El Michels Affair
- Oroza, Bobby feat. Cold Diamond & Mink
- Orozco Barrientos
- Orozco, Alejandra
- Orozco, Antonio (Spanish singer-songwriter)
- Orozco, Antonio & Fonsi, Luis
- Orozco, Antonio & Juanes
- Orozco, Antonio & KAROL G
- Orozco, Antonio & Martín, Dani
- Orozco, Antonio & Pereyra, Luciano
- Orozco, Antonio & Raphael
- Orozco, Antonio & Soledad
- Orozco, Antonio & Yatra, Sebastián
- Orozco, Antonio con Malú
- Orozco, Antonio feat. Fonsi, Luis
- Orozco, Antonio feat. Malú
- Orozco, José Darío
- Orozco, José-Luis
- Orozco, Rafael (pianist)
- Orozco, Regina
- Orozco, Verónica
- Orphan (80's band from Winnipeg, Canada)
- 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
- Orphans, The (West Chester, PA (USA) punk band)
- Orphans, The (Australian power pop)
- orphantwin
- Orpharion
- Orphax (Dutch ambient / drone musician)
- Orphean Passage
- Orphei Drängar
- Orphei Drängar, Sund, Robert
- Orpheus (Australian death metal band)
- Orpheus (1960s–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
- Orphix
- Orphx (Canadian industrial / techno project)
- ORPHY (Kirill Rogovets)
- Orplid
- Orquesta (Madrid-based duo)
- Orquesta Akokán
- Orquesta Akokán feat. Oliveros, Carolina
- Orquesta América (Cuban charanga)
- Orquesta Aragón
- Orquesta Aragón feat. Feliciano, Cheo
- Orquesta Broadway
- Orquesta Bronko
- Orquesta Calibre (Colombian salsa orchestra)
- Orquesta Caliente
