- O
- OO
- OO
- OO
- OO
- OafOak
- OaKObe
- OBEOBN
- ObnOca
- OcaOce
- OceOco
- OCSOct
- OctODD
- ODDODE
- ODEOdo
- OdoOf
- OfOff
- offOff
- OffOgr
- OGROH
- OhOhm
- OhmOiz
- OizOka
- OkaOkl
- OklOla
- OlaOld
- OldOld
- OldOle
- OleOli
- OliOli
- OliOlo
- OloOly
- OlyOm
- OmOme
- OmeOmn
- OmnON
- OnOne
- OneOne
- OneOne
- OneOne
- OneONL
- OnlOno
- onoOOJ
- OojOpa
- OpaOpe
- OpeOpp
- OppOra
- OraOra
- OraOrc
- OrcOrc
- OrcOre
- OreOrg
- OrgOri
- OriOri
- OriOrm
- OrmOrp
- OrpOrq
- OrqOrt
- OrtOsa
- OsaOsc
- OscOsk
- OskOSR
- OssOT
- OtaOti
- OtiOtt
- OttOtw
- OtwOur
- OurOut
- OutOut
- OutOut
- OutOVE
- OVEove
- Oveovr
- OvsOwe
- OweOxi
- OxiOza
- OzaOzo
- Ozoozz
- Okada, Yukiko
- Okafor, Ben
- Okakita, Ayu
- Okali
- Okaly, Kyle
- Okami Sky
- Okami, Alex (Arizona post-punk)
- Okamoto Reiji (OKAMOTO'S)
- Okamoto, Mayo
- Okamoto, Nobuhiko
- OKAMOTO’S
- OKAMOTO’S × RIP SLYME
- Okamura, Takako
- Okamura, Yasuyuki
- OKAN (Canadian afro-cuban duo)
- Okan, Cem
- Okan, Cihan
- Okan, Tanju
- Okandeji Adedayo Olamilekan
- Okapi
- Okashii
- Okasian (Korean-American rapper & singer)
- OKAWARI, DJ
- OKAWARI, DJ feat. Amadori
- OKAWARI, DJ feat. Amanda Diva
- OKAWARI, DJ feat. Campbell, Brittany
- OKAWARI, DJ feat. Kamiya, Eri
- OKAWARI, DJ feat. Meyer, Emi
- OKAWARI, DJ feat. San, Woong
- OKAWARI, DJ feat. Styler, Emily
- OKAWARI, DJ feat. Tekitha
- Okay (Marty Anderson's California indie rock project)
- OKAY (also: O.K., pop group from Frankfurt, Germany ("Okay!"))
- Okay Alright
- Okay Kaya (Kaya Wilkins)
- Okay Kaya feat. Zannie
- Okay Mann
- okayceci
- Okayracer
- okaywill (will)
- Okazaki, Ritsuko
- Okazaki, Taiiku
- Okda
- OKDAL
- Okean Elzy
- Okean Elzy, Del Naja, Robert, Vakarchuk, Svyatoslav
- Okee Dokee Brothers, The
- Okeefe, Josh
- Okehazama, Alisa
- Okehazama, Alisa
- Okello Max
- Okello Max & Bensoul
- Okello Max & Charisma
- Okello Max & Owiyo, Suzanna
- Okello Max & Watendawili
- Oker
- Okereke, Kele
- Okereke, Kele & Ejeca
- Okereke, Kele feat. Alexander, Olly
- Okereke, Kele feat. Bailey Rae, Corinne
- Oketo
- Okey Dokey (2010s psych soul)
- Okey-iwobi, Brendan
- Okey, Ixie (Ugandan pop artist)
- okgiorgio (Giorgio Pesenti)
- okgiorgio & Estremo
- okgutta
- okho
- OKI (Polish MC)
- Okills
- Okills feat. Guevara, Laura.
- Okilly Dokilly
- Okin (Indonesian musician)
- Okin, Earl
- Okinawa Lifestyle
- Okino, Shuntaro
- Okino, Shūya feat. Duplaix, Vikter
- okis (french rap)
- okis & Mani Deïz
- OKISO (oxo)
- OKISO, GUMI
- Okken, Rinus
- Okkervil River
- Okkervil River & Antlers, The
- Okkosch, Samuel
- Okktli
- Okkultist
- OKKUPADO
- Oklahoma Kid, The
- Oklahoma Uprising
