- O
- OO
- OO
- OOak
- OakObi
- ObiObt
- ObuOce
- OceOct
- OctOdd
- OddODM
- ODOOf
- OfOfn
- OfoOH
- OHOHN
- OhnOK
- OKOko
- OkrOld
- OldOld
- OldOli
- OliOll
- OllOm
- OMAOme
- OmeON
- onOne
- OneOne
- OneOne
- OneOnl
- OnlOom
- OomOpe
- OpeOpt
- OptOra
- OraOrc
- orcOre
- OreOri
- OriOrk
- OrkOrp
- OrpOrt
- OrtOsa
- OsbOSH
- OshOst
- OstOth
- OthOtt
- OttOur
- OurOut
- OutOut
- OutOve
- Oveovl
- OvnOwl
- OwlOys
- OZOZZ
- Overcoats
- Overcome (American christian hardcore)
- Overdawn
- Overdose (Brazilian metal band)
- Overdose TV
- OverDoz.
- Overdream (metal/rock)
- Overdrive (Swedish metal band)
- Overdrive (NWOBHM band)
- OverDrive Division
- Overdrive Orchestra
- Overflash
- Overflow (Croatian punk band)
- Overflow (South Carolina Christian pop/rock band)
- Overground (German boygroup)
- OVERGROUND ACOUSTIC UNDERGROUND
- Overgrown Throne (Chapel Hill, NC punk)
- Overhead (French band)
- Overhead (Finnish progressive rock band)
- Overkill (US thrash metal band fronted by Bobby "Blitz" Ellsworth)
- Overlake
- Overland (band featuring Steve Overland)
- Overland, Steve
- Overlanders, The
- Overload (Swiss Trash-Metal band)
- Overlord (Chilean melodic thrash/death metal)
- Overlorde
- Overlords, The (Danish Synth-pop / EBM / electro / techno / goa trance project)
- Overmars (French metal band)
- Overmaster (Power Metal, Alessandria, Piedmont, Italy)
- Overmono (brothers Tom & Ed Russell (Truss & Tessela))
- Overmono feat. St. Panther
- Overo
- Overpass (successor to California Punk Band 'Slovenly')
- overpass (British band, Birmingham)
- Overrides, The
- Overscene
- Overseer (English DJ/producer)
- Overseer, The (American Christian metal band)
- Overself
- Oversense
- Overshock
- Overslept, The
- OverSoul (chillout)
- OverSoul feat. Gram’ma Funk
- Overstreet (Alt-Pop-Rock project of Chord Overstreet.)
- Overstreet, Chord
- Overstreet, Paul
- Overstreet, Tommy
- Overstreet, Willard
- Overthrone
- Overtime (American hip hop/country)
- Overton, Karen
- Overtones, The (UK founded (from X Factor) vocal harmony group)
- Overtorture (Death Metal from Sweden)
- Overtoun
- Overture (Progressive Metal, Los Angeles, California, United States)
- Overtures (Italian metal band)
- Overtures (Melodic Metal)
- OVERWERK (Canadian DJ)
- OVERWERK feat. MARS
- OVERWERK feat. Nikon, Nick
- Ōverwhelm (Overwhelm)
- Overwhelming Colorfast
- Overworld
- Ovi (Ovidio Crespo, latin urban artist)
- Ovi & Arcángel
- Ovi & De Oro, Omy
- Ovi & Junior H
- Ovi & Mariah Angeliq
- Ovi & Mora
- Ovi & Rene
- Ovi & Uribe, Jessi
- Ovi & Woodz, Miky
- Ovi & Z, Jon
- Ovi, Cano, Natanael, Alemán & Big Soto
- Ovi, Cano, Natanael, Junior H & Herencia de Patrones
- Ovi, Cano, Natanael, Quiles, Justin & Play-N-Skillz
- Ovi, Carrión, Eladio, Cano, Natanael & BadGuyChapo
- Ovi, Ñengo Flow, Towers, Myke & Alemán
- Ovi, Tavárez, Lenny, Brytiago & Cano, Natanael
- Ovi, Zion & Lennox & Play-N-Skillz
- Ovianno (Solo Artist)
- Ovid's Withering
- Oviedo, Papi y sus Soneros
- Ovif
- Oviformia SCI
- Ovijay
- ovine hall (glaive's experimental project)
- ovlov (Connecticut alternative rock group)