- O
- OO
- OO
- OOak
- OakObi
- ObiObs
- ObsOce
- OceOCT
- OctODD
- OddOdm
- ODMof
- OfOff
- OffOh
- OhOHK
- OhkOjo
- OjoOki
- OkkOla
- OLAOld
- OldOli
- OliOli
- OliOls
- OlsOme
- OmeOmn
- OmnOnc
- One
- OneOne
- OneOnl
- OnlONY
- OnyOpe
- OpeOpi
- OpiOra
- OraOrb
- OrbOrd
- OrdOrg
- OrgOri
- OriOrm
- OrmOrq
- OrqOrw
- OrxOsc
- OscOsl
- OsmOsz
- OszOts
- Ots
- Out
- OutOut
- OutOut
- OutOve
- OveOwe
- OweOxf
- Oxf
- OZZ
- Orquesta Sublime
- Orquesta Tabaco y Ron
- Orquesta Típica Fernández Fierro
- Orquesta Típica Misteriosa Buenos Aires
- Orquesta Típica Tanturi
- Orquesta Todos Estrellas (Cuban orchestra (All Stars) with various artists from Egrem label)
- Orquesta Zodiac
- Orquestra Afro-Brasileira
- Orquestra Brasileira de Música Jamaicana
- Orquestra Contemporânea de Olinda
- Orquestra Imperial
- Orquestra Voadora (Brazilian brass band)
- Orquestra Was
- Orr, Benjamin
- Orr, David
- Orr, Scott
- Orrall, Robert Ellis (US country singer/producer)
- Orrantia, Hayley (US actress and singer)
- Orrason, Máni
- Orrico, Stacie
- Orrje, Carl, Piano Ensemble
- Orry Jackson (German singer and songwriter)
- Orsa spelmän
- Orselli, Folco
- Orsen
- Orsen, Jack
- Orsen, Jack & Taktloss
- Orsenna, Erik
- Orsi
- orso, L' (Italian band)
- Orsolics, Hans
- Orson (00s US power pop band)
- Orsons, Die
- Orsons, Die feat. Cro
- Orsons, Die feat. Maxim
- Orta, Choco
- Orta, Manuel
- Orta, María (Puerto Rican Christian music singer)
- Ortaç, Serdar
- Ortaçgil, Bülent
- Ortaçgil, Bülent & Kızılok, Fikret
- Ortaçgil, Bülent & Teoman
- Ortak, Svaba (rapper from Austria)
- Ortega, Anthony (jazz saxophonist)
- Ortega, Anthony, Trio
- Ortega, Emanuel
- Ortega, Fernando
- Ortega, Jeannie
- Ortega, Jeannie feat. Papoose
- Ortega, José (designer)
- Ortega, Lindi
- Ortega, Michael
- Ortega, Paco
- Ortega, Palito
- Ortegon, Sr (José Miguel Ortegón)
- Ortelli, Paolo, Matrix, DJ, Party Boomers feat. C, Jay
- Ortero, David
- Orth, Marisa
- Orthentix
- Orthodox (Spanish doom metal)
- Orthodox (Straight Edge)
- Orthodox Celts
- Orthostat
- orti (electronic/electroclash/techno project)
- Orties
- Ortiga (Chilean canto nuevo group)
- Ortiga (Former Esteban & Manuel member)
- Ortiz, Alfredo (player of the Paraguayan harp)
- Ortiz, Bill
- Ortiz, Gerardo (Regional Mexican singer)
- Ortiz, Joell (rapper fka Jo‐ell Quikman)
- Ortiz, Joell feat. Immortal Technique
- Ortiz, Joell feat. Novel
- Ortiz, Kevin
- Ortiz, Luis “Perico”
- Ortiz, Paul y La Orquesta Son
- Ortolani, Riz
- 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)
- Oruç, Mustafa
- Orup (Swedish musician Hans Thomas Eriksson)
- Orville Peck
- Orvokki
- Orwell (French band)
- Orwells, The