- O
- OO
- OO
- OO
- OO
- OOak
- OakObe
- ObeObl
- OblObs
- OBSOce
- OceOch
- OchOct
- OctOdd
- OddOde
- OdeOdi
- OdiOdy
- OdyOfe
- OfeOff
- OffOga
- OgaOh
- OhOha
- OhaOi
- OiOjo
- OjoOka
- OkaOku
- OkuOla
- OlaOld
- Oldold
- OldOle
- OleOli
- OliOli
- OLIOls
- OlsOM
- omOma
- OmaOme
- OmeOmn
- OmnOn
- OnOne
- OneOne
- OneOne
- OneOne
- OneONL
- ONLOno
- OnoOob
- OOcOP
- OpaOpe
- OpeOpp
- OppOr
- OrOra
- OraOrb
- OrbOrc
- OrcOrd
- OrdOrf
- OrfOri
- OriOri
- OriOrl
- OrlOro
- OroOrq
- OrqOrt
- OrtOrx
- OryOsb
- OsbOse
- OseOsm
- OsmOst
- OSTOte
- OteOto
- OtoOtt
- OttOu
- OuaOUR
- OurOut
- OutOut
- OutOut
- OutOve
- OveOve
- OveOvt
- OvvOwe
- OweOxh
- OxiOza
- OzaOzo
- OzoOZZ
- Ono, Yoko feat. Penguin Prison
- Ono, Yoko feat. Peter Bjorn and John
- Ono, Yoko feat. Portugal. The Man
- Ono, Yoko feat. Sparks
- Ono, Yoko feat. Tenaglia, Danny
- Ono, Yoko Plastic Ono Band
- Ono, Yoko/IMA
- Ono, Yuji (Electronic music producer and DJ)
- Ono, Yuuki
- Onoe Caponoe
- onoken
- Onokio
- Önol, Onat
- Onono, Ben
- Onorata
- Onosaka, Masaya
- Onpointlikeop
- ONR.
- Onra (French producer/beatmaker Arnaud Bernard)
- Onra feat. B, Reggie
- ONRA S (German singer-songwriter, composer and producer)
- Onrust (Dutch 2000s black metal)
- ONRUST (Belgian post-metal band)
- Onsa Media (a group of musicians, who records covers mainly and sometimes original songs and parodies also)
- ONSatan
- Onsetter
- Onsind (acoustic pop punk band)
- Onslaught (UK punk/thrash/speed metal band)
- Onslow (Alternative rock band)
- Onsoku Line
- Ontaneda, Sara
- Ontborg (Italian melodic death metal band)
- OnTheEdge
- Ontic
- ONTOGYZONEKI
- ontologics
- Ontuak
- onTune
- Onuabuobi, Victor (Nigerian gospel singer)
- Onuka
- Onuka feat. Ukrainian National Academic Orchestra of Folk Instruments
- Onuka with Ukrainian National Academic Orchestra of Folk Instruments
- Onuki, Ami
- Onuki, Taeko
- Onukwulu, Ndidi
- Önül, Abdurrahman
- Önül, Abdurrahman & Karatüre, Celal
- Onuma, Parsley
- onumi
- Onuora, Oku
- Onur Bostancı (Alternative, Pop)
- Onural, Cengiz
- Onurr
- Onward (US band)
- Onward Brass Band (Barbarin/Cottrell, 1960-)
- Onward to Olympas
- Onward, etc.
- Onyanko Club
- Onyeabor, Charles
- Onyeabor, William
- Onyioha, Oby
- Onyria (Oniria)
- Onysus
- ONYVAA
- Onyx (New York hardcore rap group)
- Onyx (Israeli psytrance DJ Yaniv Goldfarb)
- Onyx (IDM artist, track "Under Pressure")
- Onyx & Dope D.O.D.
- Onyx Collective
- Onyx feat. ASAP Ferg & Price, Sean
- Onyx feat. DMX
- Onyx feat. Dope D.O.D.
- Onyx feat. Genovese
- Onyx feat. Havoc
- Onyx feat. Makem Pay
- Onyx feat. Papoose & Cormega
- Onyx feat. Reks
- Onyx feat. Snak the Ripper
- Onyx feat. X1
- Onyx, PTX & Domestic
- Onza (Spanish prog and fusion band)
- Onza (Spanish rock band.)
- Onze‐Mots
- Onze:20
- ONZY
- OOBE (Italian techno/house producer)
- OOBE (Polish Rock Band)
- Ooberfuse
- Ooberman
- Oobik & the Pucks
