- O
- OO
- OO
- OO
- OOAF
- OAFOak
- OakObe
- OBEOBO
- OBOOcc
- OccOce
- OCEOct
- OctOCU
- OCUOdd
- OddODE
- ODEODU
- ODUOf
- OfOff
- OffOG
- OGOGX
- OhOh
- OhOHY
- OiOjo
- OjoOkd
- OKDOku
- OkuOla
- OlaOld
- OldOle
- OleOli
- OliOli
- OliOll
- OllOls
- OlsOma
- OmaOme
- OmeOmn
- OmnON
- OnOnd
- OndOne
- OneOne
- OneOne
- OneOnk
- ONLOno
- Onooof
- OogOpa
- OpaOpe
- OpOpp
- OppOra
- OraOra
- OraOrc
- OrcOrc
- OrcOre
- OreOrg
- OrgOri
- OriOri
- OriOrn
- OrnOrq
- OrqOrr
- OrsOrt
- OrtOsb
- OsbOsc
- OscOsl
- OslOst
- OstOte
- OteOtr
- OtrOtt
- OttOui
- OuiOus
- OutOut
- OutOut
- OutOuu
- OuvOve
- OveOvi
- OviOwe
- OweOwu
- OwuOya
- OyaOZI
- OZIozz
- Ortize, Brian
- Ortolan (US indie pop band on Sounds Familyre)
- Ortolani, Riz (songwriter, film music composer and music director)
- Ortolani, Riz feat. Ranieri, Katyna
- Orton, Beth
- Orton, Beth feat. Callier, Terry
- Orton, Mark
- Ortopedia Técnica (Garage Punk band from Castellón de la Plana)
- ortoPilot
- Ortsul (Poland / Black Metal)
- Oruã (Brazilian group)
- Oruam (Brazilian rapper)
- Oruç, Mustafa
- Orup (Swedish musician Hans Thomas Eriksson)
- Orus, Susan (Swiss singer)
- Örvarsson, Atli (Icelandic score composer)
- Orvis, Jayke (US singer-songwriter)
- Orvokki
- Orwell (French band)
- Orwells, The
- Orxata Sound System
- Ory, Kid
- Ory, Kid, Creole Jazz Band
- Oryad (doom metal/symphonic metal group)
- Oryema, Geoffrey
- oryl
- oryl feat. Nikki Idol
- Oryon (Dutch producer Peter Smit)
- Orzabal, Roland (UK musician, songwriter and producer)
- OS (German duo)
- OS 101
- Os 3 do Nordeste
- Os Atuais
- Os Bardos
- Os Borges
- Os Borges & Elis Regina
- Os Caçadores
- Os Carbonos (vocal group)
- Os Cretinos
- Os Dentes
- Os Druidas
- Os Extintos
- Os Farrapos
- Os Garotin
- Os Golpes
- Os Kmaradas
- Os Mateadores
- Os Mundi
- Os Nativos (South-Brazilian gaucho music group)
- Os Pontos Negros
- Os Quebradeiras
- Os Serranos
- Os The Darma Lóvers
- Os Tincoãs
- Os Trapalhões
- Os Vips
- Os Vips (Os Vips)
- OS101 (hardcore punk band)
- Osa (El Caco frontman Øyvind Osa's solo project)
- OSA (Nigerian R&B singer-songwriter)
- Osa, Liv Bernhoft (Norwegian actress)
- Osada Vida
- Osadebe, Stephen Osita, Chief
- Osaen
- Osage Tribe
- Osaka Flu
- Osaka Monaurail
- Osaka Popstar
- Osaka Punch (Australian rock band, formerly The Kidney Thieves)
- Osaka Syunkasyuto
- Osaki (jazz hop)
- Osaki ft. Sleepermane
- Osaki, Nana starring Nakashima, Mika
- Osama GBS
- OsamaSon (underground artist)
- OsamaSon feat. Che
- Osanna
- Osanzi (Composer in Japan)
- Osasioo (Canadian RnB Artist)
- Osatia
- Osawa, Shinichi
- Osay (American rapper, singer-songwriter)
- Osaze feat. Veda, Jaidene
- Osbe Chill
- Osborn, Abigail
- Osborne (Todd Osborn)
- Osborne Brothers, The
- Osborne Brothers, The & Allen, Harley "Red"
- Osborne Brothers, The & Wiseman, Mac
- Osborne, Anders (US singer-songwriter)
