- O
- OO
- OO
- OOak
- OakObe
- ObeObs
- ObsOce
- OceOct
- OctOdb
- ODCODE
- ODEODU
- OduOff
- OffOG
- OGOh
- OhOhm
- OhmOjo
- OjoOki
- OkiOla
- OlaOld
- OldOle
- OleOli
- OliOlo
- OloOMA
- OMAOme
- OmeOmu
- OMYOnD
- OneONE
- ONEone
- Oneonl
- Onlonu
- OnuOoz
- OPOph
- OphOqu
- OQuOrb
- OrbOrc
- OrcOre
- OreOri
- OriOrk
- OrkOro
- OroOrr
- OrrOry
- OryOsb
- OscOsl
- OslOst
- OstOti
- OtiOTT
- OttOur
- OurOut
- OutOut
- OutOve
- OveOVE
- OVEOwe
- OweOxm
- OxmOzo
- OzoOZZ
- Otto Dix
- Otto feat. Gilberto, Bebel
- Otto Knows
- Otto Knows feat. Avicii
- Otto Normal
- Otto Ohm
- Otto, James
- Otto, James feat. Milsap, Ronnie
- Otto, Molly
- Otto, Natalino
- Otto's Daughter
- Ottobrenero (Italian progressive metal)
- Ottolien (brother duo from Hanover)
- Ottolini, Mauro
- Ottolini, Mauro e la sua Orchestra Ottovolante
- Ottolini, Mauro, Sousaphonix
- Ottolini, Robyn
- Ottoman (Icelandic blues rock band)
- OttoMattic
- Ottone Pesante (Italian band)
- OTTTO
- Ottum, Josh
- Otu (Finnish audio engineer & musician, Moonic Productions)
- Otway, John
- Otway, John & Barrett, Wild Willy
- Otway, John & Barrett, Wild Willy
- Otyg
- Otyken (Siberian aborigine’s music group)
- Otzeki
- Ötzi (Oakland post-punk)
- Ötzi, DJ (Austrian entertainer and schlager singer)
- Ötzi, DJ & Bellamy Brothers, The
- Ötzi, DJ & Friedle, Lisa‐Marie
- Ötzi, DJ & Gott, Karel
- Ötzi, DJ & Hall, Kate
- Ötzi, DJ & Hermes House Band
- Ötzi, DJ & P., Nik
- Ötzi, DJ & P., Nik
- Où est le Swimming Pool (English synthpop group)
- Ou2s (french rapper)
- Ouai Stéphane
- Ouaipaul
- Oualid (Dutch rapper/vocalist Oualid Roshdy)
- Oub LCK
- OUBEL
- Oubéret
- Oubliette (melodic black metal band from Tennessee)
- Ouboter, Maaike
- Oud west
- Ouellet, Karim
- Ouellet, Karim feat. Sarahmée
- Ouellet, Yvan
- Ougenweide
- Ought (Canadian post-punk band)
- Oui 3
- Oui lele
- Ouija Macc
- Ouijabeard (Rock, Hardrock, Metall)
- Ouimette, Steve
- Oulton, Quinn
- Oum (Oum el Ghaït Benessahraoui)
- Oum Shatt
- Oumar (French rapper Oumar Magassa)
- Oumou Dioubate
- Oumua
- Ounsworth, Alec
- Our 11th Hour (Progressive Rock Group from Syracuse, NY)
- Our Broken Garden
- Our Brother the Native
- Our Ceasing Voice
- Our Ceasing Voice & Ryan, Matthew
- Our Dementia Choir
- our distant worlds
- Our Fears
- Our Future Leaders
- Our Girl
- Our Heart’s Hero
- Our Hollow, Our Home
- Our Lady Peace
- Our Lady Peace feat. Jones, Elvin
- Our Lady Peace feat. Pussy Riot
- Our Lady Peace featuring Jones, Elvin
- Our Last Enemy (industrial metal)
- Our Last Night
- Our Little Secrets
- Our Loss Is Total
- Our Lost Infantry (Progressive/Post-rock/Pop)
- Our Man in the Bronze Age
- Our Martyred Lady
- Our Mirage
