- O
- OO
- OO
- OO
- OOaf
- OAFOaK
- OakObe
- ObeOBO
- Obo
- OcaOce
- OceOCT
- OctOct
- OctOdd
- oddODE
- ODEOdo
- OdoOf
- OfOFF
- OffOfi
- OfiOgr
- OgrOh
- OhOhn
- OhnOJ
- OJOka
- OKAOko
- OkoOla
- OlaOld
- OldOld
- OldOle
- OleOli
- OliOli
- OliOls
- OlsOma
- OmaOmb
- OMBOMI
- OMIOmo
- OmoOnc
- OncOne
- OneONE
- OneONE
- OneONF
- OnFOnl
- OnlOnu
- OnuOom
- OomOpe
- OpeOph
- OphOpu
- OpuOra
- OraOrb
- OrbOrc
- OrcOrc
- OrdOre
- OreOri
- OriOri
- OriOrl
- Orl
- OroOrq
- OrqOrs
- ORTOrw
- OrwOsb
- OsbOse
- OseOsm
- OsmOst
- OstOth
- OthOtr
- OTROtt
- OttOum
- OumOut
- OUTOut
- OutOut
- OutOuv
- OUWOVE
- OveOvi
- OviOwe
- OweOwu
- OwuOya
- OyaOzi
- oziozz
- Ohno, Eri
- Ohno, Katsuo
- Ohno, Katsuo & Ohno, Katsuo
- Ohno, Yuji (anime music composer and jazz pianist)
- Ohno, Yuji & Lupintic Five
- Ohno, Yuji & Lupintic Five with Friends
- Ohno, Yuji & You & The Explosion Band
- Ohno, Yuji, Trio
- OhNos, The
- OHO (Trip-Hop/Folk/Electronica)
- OHO
- Oho, The (Finnish band)
- OHora, Zephaniah
- OHR (Seattle based psych solo project of Craig Klein.)
- Ohrage
- Ohrbooten
- Ohrenfeindt
- Ohta, Mitsuhiro
- Ohtaki, Eiichi
- Ohtani, Tomoya, Eguchi, Takahito feat. Barnitt, Quinn
- Ohtar (Polish black metal)
- Ohtis
- Ohuchi, Yoshiaki
- ohyeahsumi
- OHYUNG
- OHYUNG & STEFA*
- Oi Polloi
- Oi Va Voi (British band)
- Oi Va Voi feat. Zinger, Earl
- Oi-Melz
- Oi-Skall Mates
- Oi! Scouts, The (Oi band from USA)
- Oi! Se Arma (Islas Canarias)
- Oi! The Arrase
- OID (Indie Vocaloid Musician)
- Oídos Fresh, Los
- Oigăn (Eugen Nuțescu)
- Óige
- Õigemeel, Birgit
- Oihenart, Maddi (Basque singer)
- OIIO (Dutch indie folk band)
- OIJ (Dutch musician Valentijn Crouwel)
- Oikawa, Mitsuhiro
- Oiki (dubstep artist)
- Oïkoumen (French symphonic metal band)
- Oil (Bolivian Rock Band)
- Oil (Hard Rock band from Lahr in Germany)
- Oil 10
- Oil Barons, The
- Oil Boom
- Oil Giant
- Oil on Canvas (Daggers, Hoffmann)
- Oiling Boiling Rhythm ’n’ Blues Band
- Oilix
- Oimara
- Oimara (aka Benedikt Hafner)
- Oinas, Nuppu feat. Bee, Sara
- Oingo Boingo
- OIO (polish Hip-Hop trio (OKI, Igi, Otsohodzi))
- OiOai (Portuguese pop-rock band)
- OIR A RIO
- Oirabot
- Oiseaux-Tempête
- Oishi, Masayoshi
- Oisín (70/80s Irish Celtic Folk)
- Oisin (Argentinian nu metal band)
- Oister Boy (Minneapolis grunge punk band)
- Oistrakh, David Fiodorovich (violinist)
- Oistrakh, David Fiodorovich, Berliner Philharmoniker
- Oistrakh, David Fiodorovich, Moscow Philharmonic Orchestra, Rozhdestvensky, Gennadi Nikolayevich
- Oistrakh, David Fiodorovich, Oborin, Lev, Knushevitsky, Sviatoslav
- Oistrakh, David Fiodorovich, State Academic Symphony Orchestra of the Russian Federation, Kondrashin, Kirill
- Oistrakh, David Fiodorovich, Yampolski, Vladimir
- Oistrakh, David Fiodorovich, Yampolsky, Vladimir
- Oito7Nove4
- Oizo, Mr. (Quentin Dupieux)
- Oizo, Mr. & Phra
- Oizo, Mr. feat. Bart B More
- Oizo, Mr. feat. Boys Noize
- Oizo, Mr. feat. Castro, Carmen
- Oizo, Mr. feat. Charli xcx
- Oizo, Mr. feat. Peaches
- Oizo, Mr. feat. Phra
- Oizo, Mr. feat. Siriusmo
- Oizo, Mr. feat. Skrillex
- Oizo, Mr. feat. Uffie
- Oizo, Mr., Phra & Frah Quintale
- Oizone
- OJ da Juiceman
- OJ da Juiceman & Gorilla Zoe
