- O
- OO
- OO
- OOak
- OakObi
- ObiObt
- ObuOce
- OceOct
- OctOdd
- Oddodo
- OdoOfa
- Ofaoft
- OGOh
- OhOhn
- OhnOK
- OKOkt
- OktOld
- OldOle
- OleOli
- OliOll
- OllOma
- OmaOme
- OmeOn
- OnOne
- OneOne
- OneOne
- OneOno
- OnoOom
- OomOpe
- OpeOpu
- OpuOra
- OraOrc
- OrcOre
- OreOri
- OriOrl
- OrlOrp
- OrpOrt
- OrtOsb
- OsbOsi
- Osi
- OstOti
- OtiOtt
- OttOur
- OurOut
- OutOut
- OutOve
- OveOVT
- OvyOwn
- OwsOzb
- OZZ
- October Dogs
- October Drift
- October Ends
- October Fall (piano-fueled pop punk band)
- October Falls (Finnish atmospheric black metal)
- October File
- October Light
- October London
- October Noir
- October Project
- October Rage
- October Sky
- October Tide
- Octobre (rock band from Quebec)
- Octobre Rouge (French rap group)
- OctoLab
- Octopus (UK britpop group)
- Octopus (1970s German progressive rock group)
- Octopus (1970s Belgian pop band)
- Octopus (Progressive metal band from Chile)
- Octopus (1970s British psychedelic pop band)
- Octopus (1970s UK psychedelic rock band from Hatfield)
- Octopus Montage
- Octopus Project, The
- OCTPATH
- Octubre (spanish power-pop)
- OCULA
- OCULA feat. Tailor
- Oculist, The
- Oculos (Death/Thrash Metal band from Turkey)
- Oczojebny, Jakub
- OD Kokemus
- OD404
- ODA (Pop Singer)
- Oda, Kaori (KAORI for Yuki Kajiura)
- Oda, Kazumasa
- Oda, Tetsurou
- Oda, Yuji
- Odal (German pagan black metal band)
- Odani, Misako
- Odar
- Odawas
- Odbicia, W Witrynach
- ODC (Modern Rock and Metal project created and led by Celia Do)
- Odd (Norwegian singer/songwriter Odd Nordheim)
- Odd (Filipino post-rock band from Dumaguete)
- Odd Beholder (Swiss pop duo)
- Odd Børre
- Odd Chap
- Odd Couple (house artist)
- Odd Couple (rock ’n’ roll)
- Odd Couple, The (US hip-hop duo Louis Logic & Jay Love)
- Odd Crew
- ODD EYE CIRCLE (South Korean girl group)
- Odd Future
- Odd Logic (US prog rock/metal)
- Odd Mob
- Odd Mob feat. Blackman, Bertie
- Odd Nosdam
- Odd Nosdam feat. Bailiff, Jessica
- Odd Numbers, The
- Odd Palace
- Odd Project
- Odd Signature (Bangladeshi Band)
- Odd Squad
- Odd Sweetheart
- Odd Thomas (Thomas Joseph Terry)
- Oddateee
- oddCouple feat. Woods, Jamila & Collins, Kweku
- ODDEEO
- Oddessey
- Oddfellows, The (The Oddfellows (Singapore Band))
- OddHenny
- Oddisee (DC hip hop producer/rapper)
- Oddisee feat. Diamond District
- Oddisee feat. Ragu, Priya & Sainte Ezekiel
- Oddisee feat. Real, Ralph
- Oddisee feat. Saint Louis, Olivier
- Oddisee feat. Saint Louis, Olivier
- Oddisee feat. Toine
- Oddisee feat. Toine & Trek Life
- Oddities
- OddKidOut
- Oddko (Los Angeles based Industrial Metal band)
- Oddland
- oDDling
- ODDLIQUOR
- Oddly
- Oddly Casual
- Oddprophet