- O
- OO
- OO
- OOak
- OakObi
- ObiObt
- ObtOce
- OceOct
- OctOdd
- OddODO
- ODOOf
- OfOfn
- OfoOh
- OhOhm
- OhmOK
- OKOKO
- OkoOla
- OlaOld
- OldOli
- OliOll
- OllOly
- OlyOme
- OmeOmp
- OMROne
- OneONE
- OneOne
- OneOnl
- OnlOoj
- OokOpe
- OpeOpp
- OPROra
- OraOrc
- OrcOre
- OreOri
- OriOri
- OriOrp
- OrpOrt
- OrtOsa
- OsaOsh
- oshOss
- OssOth
- OthOtt
- OttOur
- ourOut
- OutOut
- OutOve
- OveOvi
- OviOwl
- OwlOy
- OyaOzu
- OzuOZZ
- Orchestra
- Orchestra (Hot Spot Orchestra)
- Orchestra Bagutti
- Orchestra Baobab (Senegalese Afro-Cuban band)
- Orchestra Capri
- Orchestra Città di Ferrara
- Orchestra del Teatro alla Scala di Milano, Serafin, Tullio
- Orchestra del Teatro dell’Opera di Roma
- orchestra di Piazza Vittorio, L’
- ORCHESTRA FUEGO
- Orchestra Harlow
- Orchestra JB
- Orchestra Marrabenta Star de Moçambique
- Orchestra Marrabenta Star de Moçambique feat. Wazimbo
- Orchestra Morphine
- Orchestra Mozart
- Orchestra of Syrian Musicians, The
- Orchestra of the Mariinsky Theatre, Gergiev, Valery
- Orchestra of the Royal Opera House, Covent Garden
- Orchestra Rosichino (Grande Orchestra Rosichino)
- Orchestra Spettacolo Casadei
- Orchestra Super Mazembe
- Orchestra, Bert Kaempfert
- Orchestra, Big Time
- Orchestra, Bone Poets
- Orchestra, Chennai
- Orchestra, Moka Efti (Music from the 20s)
- Orchestra, Puente, Tito's
- Orchestraccia
- Orchestral Manoeuvres in the Dark
- Orchestre de l’Opéra national de Paris, Prêtre, Georges
- Orchestre de l’Opéra national de Paris, Prêtre, Georges
- Orchestre de la Société des Concerts du Conservatoire, Cluytens, André
- Orchestre de la Société des concerts symphoniques de Paris, Leibowitz, René
- Orchestre de la Suisse Romande, Ansermet, Ernest
- Orchestre de la Suisse Romande, Ansermet, Ernest
- Orchestre de Paris, Karajan, Herbert von
- Orchestre Ducoin
- Orchestre International du Vetex (Belgian brassband)
- Orchestre National de Barbès
- Orchestre national de France, Maazel, Lorin
- Orchestre national du Capitole de Toulouse, Plasson, Michel
- Orchestre national du Capitole de Toulouse, Plasson, Michel
- Orchestre philharmonique de Paris, Cosma, Vladimir
- Orchestre Tout Puissant Marcel Duchamp
- Orchid (United States screamo band)
- Orchid (American doom metal group)
- Orchid (eldia associate)
- Orchid feat. Funk, Simply
- Orchids, The (Sarah Records)
- Orchids, The (Kim Fowley managed group)
- Orcivus
- Orcus (Philadelphia)
- Orcustus (Norwegian black metal)
- Ord, Boris
- Ord, Maren
- Orden Mundial
- Orden Ogan
- Ordén, Janne
- Order (Norwegian Black Metal)
- Order From Chaos
- Order of Apollyon, The
- Order of Elijah, The (Joplin, MO)
- Order of Ennead
- Order of Israfel, The
- Order of the Ebon Hand (Greece / Black Metal)
- Order of the Fly, The
- Order of Týr
- Order of Voices
- Order89 (Parisian darkwave trio)
- Ordge, Jimmy Arthur (Canada)
- Ordinaires, The (USA band)
- Ordinance (USA progressive death metal)
- Ordinarius
- Ordinary Boys, The
- Ordinary Elephant
- Ordinary People (New Jersey)
- Ordinary Surfers
- Ordinary Time
- Ordo Equilibrio
- Ordo Equitum Solis
- Ordo Rosarius Equilibrio
- Ordo Rosarius Equilibrio feat. Spiritual Front
- Ordog (doom metal band from Finland)
- Ordonówna, Hanka
- Ordorika, Ruper
- Ordos (Swedish stoner/metal)
- Oré (French hip-hop/chanson/neo soul rapper/vocalist)
- Orealis
- Orebolo (Norwalk, CT indie band)