- O
- OO
- OO
- OOak
- OakObi
- ObiObs
- ObsOce
- OceOct
- OctOdd
- OddOde
- OdeOef
- OehOff
- OffOgd
- OgdOh
- OhOi
- OiOk
- okOku
- OkuOld
- OldOld
- OldOli
- OliOli
- OliOls
- OlsOMB
- OMBOmn
- OmnO
- OnaOne
- OneOne
- OneOng
- OngOno
- OnoOom
- OomOpe
- OpeOpt
- optOra
- OraOrc
- OrcOrd
- OrdOrh
- OrhOri
- OriOrm
- OrmOrq
- OrqOrt
- OrtOsb
- OsbOsi
- OsiOst
- OstOth
- OthOtt
- OttOur
- OurOut
- OutOut
- OutOve
- OveOve
- OveOwe
- OweOxl
- OxlOzm
- OZMOZZ
- Ottavo Padiglione
- Ottawa (Indie Band)
- Ottawan
- Ottawans
- Otten, Mark
- Otten, Paul (singer/songwriter)
- Otten, Thomas (French countertenor)
- Otter, Anne Sofie von (mezzo-soprano)
- Otter, Anne Sofie von & Costello, Elvis
- Otter, Anne Sofie von & Mehldau, Brad
- Otter, Till
- Ottesen, Janove
- Ottewell, Ben
- Ottman, John
- Otto (Brazilian singer)
- Otto (UK singer-songwriter Christian Punter)
- OTTO (Otto Benson)
- 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 & P., Nik
- Ötzi, DJ & P., Nik
- Où est le Swimming Pool (English synthpop group)
- Ou2s (french rapper)
- Ouai Stéphane
- 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
