- O
- OO
- OO
- OOak
- OakObi
- ObiOBS
- ObtOce
- OceOct
- OctOdd
- OddOdm
- ODMOf
- OfOFK
- OfMOh
- OhOhm
- OhmOjo
- OKOkl
- OklOla
- OlaOld
- OldOli
- OliOli
- OliOly
- OlyOme
- OmeOmo
- OMOOnd
- OndOne
- ONEOne
- OneOnl
- OnlOob
- OobOpe
- OpeOpp
- OppOra
- OraOrc
- OrcOrd
- OrdOrh
- OriOri
- OriOro
- OroOrr
- OrsOs
- OsOsc
- Oscoso
- OsoOte
- OteOtt
- OttOui
- OuiOut
- OutOut
- OutOve
- OveOVE
- Owe
- OweOXO
- Oxo
- OZZ
- Orion Experience, The
- Orion Riders
- orion sun
- Orion the Hunter
- Orion Too (Belgian 2000s trance project)
- Orion Too feat. Caitlin
- Orión XL (Argentine Rapper)
- Orion, DJ (Electro/Cumbia)
- Orion's Reign
- Orionix
- Orions Belte (Norwegian instrumental band)
- Orions Belte feat. Aase, Sigrid
- Orions Belte feat. Lerche, Sondre
- Orishas (cuban hip hop group)
- Orishas feat. Buenaventura, Yuri
- Orishas feat. Niko Noki
- Orishas feat. Passi
- Orixa
- Orka
- Orkan (Swedish prog rock)
- Orkest
- Orkest Zonder Naam
- Orkesta Mendoza (Indie Mambo)
- Orkhan Efendi
- ORKID (Swedish singer)
- Orkidea (Finnish DJ / producer Tapio Hakanen)
- Orkiestra Dni Naszych
- Orkiestra Uliczna Z Chmielnej
- Orko (UK rock band)
- Orko the Sycotik Alien
- Orkrist
- Orlandi, Violet
- Orlandi, Violet feat. Dan Vasc
- Orlando (Belgian tech house singer)
- Orlando (Italian italo-dance project)
- Orlando Julius (Nigerian saxophonist, singer, bandleader, and songwriter)
- Orlando Marin & His Orchestra
- Orlando Philharmonic Orchestra
- Orlando Pops Orchestra
- Orlando Pops Orchestra & Lane, Andrew
- Orlando Riva Sound
- Orlando Vera Cruz
- Orlando, Bobby (US record producer, indie record label owner, songwriter & musician)
- Orlando, Courtney (singer-songwriter, FKA J.R.)
- Orlando, Johnny (Canadian singer-songwriter, vlogger and actor)
- Orlando, Johnny (reggae artist)
- Orlando, Johnny & BENEE
- Orlando, Johnny & kenzie
- Orlando, Ramón
- Orlando, Tom (artist from Ottawa, Ontario, Canada)
- Orlando, Tony
- Orlando, Tony & Dawn (1970s pop group)
- Orlane
- Orleans
- Orleya
- Orlik (czech Oi!)
- Orloff, Peter
- Orloge Simard
- Orlons, The
- 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
- Orme, Le
- Ormonde
- Orna
- Ornament (Afghan Whigs and Marcy Mays)
- Ornaments (Italian band)
- Ornatos Violeta
- Orne
- Ornelas, Raúl
- Ornella Napolitani
- 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
- Öröm
- Oropesa, Omar (Christian music singer)
- Ôros Kaù (Belgian black metal)
- Oroza, Bobby
- Oroza, Bobby feat. Cold Diamond & Mink