- Ost & Kjex
- Ostbahn Kurti & Die Chefpartie
- Osticles
- Ostkreutz
- Ostrobothnian Chamber Orchestra and Kangas, Juha (conductor)
- Osunlade
- Oswald Marianne
- Oswald Sattler
- Oswaldo Montenegro
- Oswando
- Oswin Chin Behilia
- Osymyso
- Otaku
- Otello Savoia
- Otep
- Otfried Preußler
- OTH
- Other Men My Age
- Other Two
- Otis Redding
- Otis Rush
- Otis Rush and Little Walter
- Otis Spann
- Otis Spann;Fleetwood Mac
- Otros Aires
- Ottavio Dantone
- Ottavo Padiglione
- Ottawan
- Ottetto Classico Italiano
- Ottetto di archi e fiati dell'Orchestra Sinfonica Nazionale della Rai
- Ottmar Liebert
- Ottmar Liebert & Luna Negra
- Ottmar Liebert + Luna Negra
- Otto Ackermann, Solomon, The Philharmonia Orchestra
- Otto Klemperer, Ferrier, Jo Vincent
- Otto Klemperer, L'Orchestre des Concerts Lamoureux, Wiener Philharmoniker
- Otto Klemperer, Rias Symphony Orchestra, Wiener Symphoniker
- Otto Klemperer, Wiener Symphoniker
- Otto Klemperer, Wiener Symphoniker, Elsa Calti, Anton Dermota
- Otto Ohm
- Otto von Schirach
- Otto Von Schirach.
- Ottodix
- Ottoman Military Project
- Ougenweide
- Oulad Hammou Sanae
- Ouled Jouini
- Oum Kalsoum
- Oum Kalthoum
- Oum' kardoh
- Oumou Dioubaté
- Oumou Sangare
- Our Lady Peace
- Our Last Night
- Our New Orleans
- Ouroboros
- Ours
- Ours (2)
- Ousmane Doumbia dit Samba Oussou
- Ousmane Touré
- Out
- Out Hud
- Out of Eden
- Out of Office
- Out of Order
- Out of the Blue
- Outbrave
- Outcast
- Outcasts
- Outerlimitz
- OuterSpace
- OutKast
- OutKast Featuring Sleepy Brown
- OutKast with B-Real
- Outlandish
- Outlandish;Isam Bachiri;Lenny Martinez;Waqas Qadri
- Outlawz
- Outlier
- Outlines
- Outmatch
- Output Feat. Nikol Kollars
- Outputmessage
- Outrage
- Outrowz ft New-G
- Outsidaz
- Outside
- Outsider
- Outwork
- Outwork feat. Mr Gee
- Oval
- Ove-Naxx
- Over the Rhine
- Overdrums
- Overhead
- Overkill
- Overload
- Overlook Hotel
- Override
- Overseer
- Overstep