- O
- OO
- OO
- OO
- OOak
- OakObe
- ObeObr
- ObrOcc
- OccOce
- OceOct
- OctODD
- ODDODE
- ODEOdr
- OdrOfb
- OfdOff
- OffOgf
- OghOh
- OhOHN
- OHNOje
- OjeOka
- OKAOku
- OkuOla
- OlaOld
- OldOle
- OleOli
- OliOli
- OllOls
- OlsOm
- OmOme
- OmeOMO
- OmoOnc
- OncOne
- OneOne
- OneOne
- OneONL
- ONLOnr
- OnrOol
- OolOpe
- OpeOpi
- OpiOqu
- OquOra
- OraOrb
- Orborc
- orcORE
- OREOri
- OriOri
- OriORM
- OrmOrp
- OrpOrs
- OrsOrv
- OrvOsb
- OsbOse
- OseOsm
- OsmOsu
- OsvOth
- OthOtt
- OttOua
- OuaOur
- OurOut
- OutOut
- OutOva
- OVAove
- oveOVX
- OvyOwl
- OwlOxm
- Oxm
- ozz
- Once Monsters, Adams, Chloe
- Once Never Again (Belgian late 1990s hardcore band)
- Once Nothing
- Once Tiros
- Once Upon a Dead Man
- Once Upon a Time (lead Bruno Adams)
- Once upon a winter
- Once, The
- Öncel, Nazan
- OnCue
- Ond Cirkel
- Onda (Michaelangelo L'Acqua & Gregg Fine)
- Onda Sabanera
- Onda Vaga
- Onda Vaga & Serrano, Jorge
- Onda Vaselina
- Onda, Carlo
- Onda, Naoyuki
- Ondara, J.S.
- Ondas Marteles, Las
- Ondatrópica
- Önder (Dutch-Turkish rapper Önder Doğan)
- Onderadio
- Onderwater, Jeska
- Ondfødt (Finnish black metal band)
- Ondina (eurodance vocalist)
- Ondolindë (Turkish Melodic Death Metal)
- 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. Bazil
- OnDubGround feat. Brother Culture
- One (Greek/Cypriot pop boyband)
- One (Florida hard rock band)
- One (Canadian reggae group)
- 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 Choice
- One Click Straight (Alternative Filipino Band)
- One Cool Guy
- One Dae
- One Day (Australian hip-hop)
- One Day Alive (Heavy Metal Band)
- One Day as a Lion
- One Day Hero
- One Day Remains
- One Day Remains (Based in Switzerland)
- One Dead Three Wounded
- One Desire (Melodic rock band from Finland)
- One Dimensional Creatures (Manchester, UK - alt punk/post-punk/grunge)
- One Dimensional Man
- One Direction (English‐Irish pop boy band)
- One Dollar Short
- One Dove
- ONE DRAFT
- One Drop (reggae group)
- One dying wish (Italian band)
- One eskimO
- One Eye Closed
- One Eyed Moon (garage/punk/stoner rock band from Atlanta, Georgia)
- One Fall
- One Fine Day (German rock/punk band)
- One Flew South
- One Flew West
- One for All (Jazz Group)
- One for the Team
