- O
- OO
- OO
- OOak
- OakOb
- ObeObo
- OBOOce
- OceOch
- OchOct
- Odd
- OddODM
- ODOOf
- OfOff
- OFFOgr
- OgrOh
- OhOIR
- OirOKA
- OkaOku
- OkuOla
- OlaOld
- OldOli
- OliOli
- OliOls
- OlsOMA
- OmaOme
- OmeOmo
- OMPOnd
- One
- OneOne
- OneOni
- OniOno
- OnoOom
- OomOpe
- OpeOpp
- OppOra
- OraOrb
- OrbOrc
- OrcOrg
- OrgOri
- OriOrk
- OrkOrp
- OrpOrr
- OrrOrv
- OrvOsb
- OsbOsi
- OsiOst
- OstOth
- OthOtt
- OttOue
- OugOut
- OutOut
- OutOut
- OutOve
- OveOVR
- ovrOwl
- OwlOxx
- OxyOZR
- ozz
- Outspoken (Hardcore, original band from 1990)
- Outspoken, We
- Outta Control (Canadian euro dance project)
- Outta Pocket (Bay Area Hardcore)
- Outtrigger
- Outwild
- Outwork
- Outwork feat. Gee, Mr.
- Outworld (American Progressive Metal Band)
- Ouu
- Ouviña, Dante
- Ouvindo
- Ouvrard, Gaston (fils)
- Ouzo Bazooka
- Ov Hell
- Ov Lustra
- Ov Moros
- Ov Ruin
- Ov Sulfur
- Ov Sulfur feat. Jones, Howard
- Ov Sulfur feat. Medina, Kyle & Schoolcraft, Lindsay
- Ov Sulfur feat. Taylor Barber
- Ov Sulfur feat. Terrible, Alex
- OV7
- Oval Opus
- Ovall
- Ovalle, Iván
- OVAN (Korean rapper)
- Ovations, The (US vocal group from New Jersey)
- OVCOCO
- OvDeth
- OVE (indie‐pop band from Hamburg, Germany)
- Ovejas Negras, Las
- Ovejas Negras, Las feat. Ñengo Flow
- Ovenden, Julian & McPhee, Katharine
- Ovens
- OVER ARM THROW
- Over Easy (American DJ/Producer Duo)
- Over It
- Over My Dead Body
- Over My Dead Name
- Over October (Filipino pop/alternative rock band)
- Over the Bridge
- Over the Garden Wall (Animated TV Show)
- Over the Moon (French pop duo)
- Over the Ocean (from New York, USA)
- Over the Rhine
- Over the Wall (Glasgow, Scotland)
- Over, Lary
- Over, Lary & Darell
- Over, Lary & Ñejo
- Over, Lary, Amenazzy & Farruko
- Overall, Kassa
- Overall, Kassa feat. Brown, Danny & Wiki
- Overall, Kassa feat. Croker, Theo
- Overall, Kassa feat. Hakim, Nick & Croker, Theo
- Overall, Kassa feat. Hoard, J.
- Overall, Kassa feat. Iyer, Vijay
- Overall, Kassa feat. Lil B, Shabazz Palaces & Francis and the Lights
- Overall, Kassa feat. Mvula, Laura & Francis and the Lights
- Overboard
- Overboard (a cappella group)
- Overcast (US metalcore band)
- 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
- Overdrivers
- Overflash
- Overflow (Croatian punk band)
- Overflow (South Carolina Christian pop/rock band)
- Overground (German boygroup)
- OVERGROUND ACOUSTIC UNDERGROUND
- Overhand, Sam
- 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 thrash metal band)
- Overlord (Chilean melodic thrash/death metal)
