- 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
- Öncel, Nazan
- OnCue
- Onda (Michaelangelo L'Acqua & Gregg Fine)
- Onda Sabanera
- Onda Vaga
- Onda Vaselina
- Onda, Carlo
- Onda, Naoyuki
- Ondara, J.S.
- Ondatrópica
- Önder (Dutch-Turkish rapper Önder Doğan)
- Onderadio
- Ondina (eurodance vocalist)
- Ondra, Jakub (Czech vocalist, guitarist and songwriter)
- Ondrasik, John
- Ondreaz
- Ondřej Havelka a jeho Melody Makers
- Ondskapt (Swedish black metal)
- Ondt Blod (Norwegian hardcore punk band)
- OnDubGround
- OnDubGround feat. Brother Culture
- One (Greek/Cypriot pop boyband)
- One (Florida hard rock band, affiliated with Sevendust)
- One (UK rap crew, w/ members Sway, Pyrelli, etc.)
- One (UK late 60s psychedelic rock band)
- ONE (South Korean rapper)
- One (80s UK band with Steve Hovington & Seven Webster)
- One 2 (US rapper)
- One 2 Many
- ONE 3rd NOTES
- One Acen
- One Acen feat. WSTRN
- One Adam 12
- One AM Radio, The
- One America (One America)
- One Bad Pig
- One Bad Son
- One Be Lo
- One Be Lo feat. Decompoze
- One Be Lo feat. Kadi
- One Bit & Cyrus, Noah
- One Block Radius
- One Buck Short
- One Chance
- One Chance feat. Fabo
- One Click Straight (Alternative Filipino Band)
- One Cool Guy
- One Day (Australian hip-hop)
- One Day Alive (Heavy Metal Band)
- One Day as a Lion
- One Day Hero
- One Day Remains (Based in Switzerland)
- One Dead Three Wounded
- One Desire (Melodic rock band from Finland)
- One Dimensional Creatures
- One Dimensional Man
- One Direction
- One Dollar Short
- One Dove
- ONE DRAFT
- One Drop (reggae group)
- One eskimO
- One Eye Closed
- One Eyed Moon (garage/punk/stoner rock band from Atlanta, Georgia)
- One Fine Day (German rock/punk band)
- One Flew South
- One Flew West
- One for All (Jazz Group)
- One for the Team
- One for the Team (Indie Rock band from Minneapolis MN)
- One Hello World
- One Hit Wonder (California punk band)
- One Hope
- One Hundred Hours
- One Hundred, The
- One I Cinema
- One in a Million (1960s Scottish psychedelic band)
- One in a Million (Dutch rock/ska band)
- One In The Chamber (Rock Band)
- One Inch Giant
- One Inch Punch (grunge/hip hop duo from Los Angeles)
- One King Down
- One Last Glance
- One Last Wish
- One Less Reason
- One Life Crew
- One Light Out
- One Machine
- One Man
- One Man and His Droid