- 1. O Trio do Brasil
- 2. O'Connor, Hazel
- 3. O'Hara, Eureka
- 4. O-Zone
- 5. o.n.a.
- 6. O.N.C.E.
- 7. O.S.T.R.
- 8. Oakenfold, Paul
- 9. Oasis
- 10. Oba Rowland
- 11. Obel, Agnes
- 12. Obispo, Pascal
- 13. Obituary
- 14. OBK
- 15. Obrint Pas
- 16. Obscurity
- 17. Öçal, Burhan
- 18. Oceán
- 19. Ocean Alley
- 20. Ocean Blue, The
- 21. Ocean Colour Scene
- 22. Ocean Drive
- 23. Ocean Park Standoff
- 24. Ocean Wisdom
- 25. Ocean, Billy
- 26. Oceano
- 27. Oceans
- 28. Oceans Red
- 29. Octavian
- 30. Oddisee
- 31. Odell, Tom
- 32. OdESSA
- 33. ODESZA
- 34. Odetta
- 35. Odisea
- 36. Odua, Yaniss
- 37. ODV, Timo
- 38. Odyssey
- 39. Oesch's die Dritten
- 40. Of Mice & Men
- 41. Of Monsters and Men
- 42. of Montreal
- 43. Of The Wand & The Moon
- 44. Ofenbach
- 45. OFFAIAH
- 46. Offishall, Kardinal
- 47. Offset
- 48. Offspring, The
- 49. OGRE
- 50. Oh Wonder
- 51. Oh, Sleeper
- 52. ohGr
- 53. Ohio Express
- 54. OHL
- 55. OIAM
- 56. Ojos de Brujo
- 57. OK Go
- 58. OK KID
- 59. Okmalumkoolkat
- 60. Olaf (der Flipper)
- 61. Olamide
- 62. Olcay, Zuhal
- 63. Old Crow Medicine Show
- 64. Old Dominion
- 65. Oldelaf
- 66. Oldfield, Mike
- 67. Ole Ivars
- 68. Oleska
- 69. Olexesh
- 70. Oli P.
- 71. Olivas, Alfredo
- 72. Ollie & Jerry
- 73. Ölmez, Orhan
- 74. Olomidé, Koffi
- 75. Olympic
- 76. Olympic Ayres
- 77. Ol’ Dirty Bastard
- 78. Ol’ Skool
- 79. Omarion
- 80. OMB Peezy
- 81. Ombladon
- 82. OMC
- 83. Omega
- 84. Omega Lithium
- 85. OMFG
- 86. OMI
- 87. Omni
- 88. Omnia
- 89. Omnitica
- 90. Önal, Füsun
- 91. Öncel, Nazan
- 92. One Bad Son
- 93. One Direction
- 94. One Dollar Short
- 95. ONE OK ROCK
- 96. One System
- 97. One Way
- 98. One, Albert
- 99. Oneida
- 100. OneRepublic
- 101. Onete, Dona
- 102. Only Real
- 103. Onyria
- 104. Onyx
- 105. Onze:20
- 106. Ookay
- 107. Oomph!
- 108. Oonagh
- 109. Open Mike Eagle
- 110. Opera IX
- 111. Opera Magna
- 112. Opiuo
- 113. Opposites, The
- 114. Oppressed, The
- 115. Opus III
- 116. Ora, Rita
- 117. Orange Orange
- 118. Orb, The
- 119. Orbison, Roy
- 120. Orbit, William
- 121. Orbiter
- 122. Orchestral Manoeuvres in the Dark
- 123. Oreiro, Natalia
- 124. Oreja de Van Gogh, La
- 125. OrelSan
- 126. Orff, Carl
- 127. Orhan, Mahmut
- 128. Orianthi
- 129. Oriente
- 130. Original Naabtal Duo
- 131. Orkidea
- 132. Orlando, Ramón
- 133. Orme, Le
- 134. Orozco, Antonio
- 135. Orphaned Land
- 136. Orquesta Típica Victor
- 137. Orsons, Die
- 138. Ortaç, Serdar
- 139. Orthodox Celts
- 140. Ortíz, Gerardo
- 141. Ortiz, Joell
- 142. Orton, Beth
- 143. Oryema, Geoffrey
- 144. Osborne Brothers, The
- 145. Osborne, Joan
- 146. Osbourne, Ozzy
- 147. Oscar and Wolf, The
- 148. Oshun
- 149. Osiris, YK
- 150. Oswald
- 151. Otherview
- 152. Otilia
- 153. Otis Stacks
- 154. Otros Aires
- 155. Otsochodzi
- 156. Ott, Kerstin
- 157. Otto, James
- 158. Ötzi, DJ
- 159. Ouellet, Karim
- 160. Oum
- 161. Our Lady Peace
- 162. Our Last Night
- 163. Our Mirage
- 164. Outen, van, Denise
- 165. Outfield, The
- 166. Outhere Brothers, The
- 167. OutKast
- 168. Outlandish
- 169. Outlawz
- 170. OV7
- 171. Overstreet, Paul
- 172. OVERWERK
- 173. Owen
- 174. Owens, Buck, and His Buckaroos
- 175. Owl City
- 176. Ownglow
- 177. Owsey
- 178. Oxa, Anna
- 179. Oxmo Puccino
- 180. Özbey, Merve
- 181. Ozcan, Ummet
- 182. Özen, Gökhan
- 183. Özer, Zerrin
- 184. Özgün
- 185. Ozols
- 186. Ozuna
- 187. O‐Town
- 188. O’Brien, Olivia
- 189. O’Connor, Sinéad
- 190. O’Day, Anita
- 191. O’Jays, The
- 192. O’Neal, Alexander
- 193. O’Sullivan, Gilbert