- 1 OCTOBER
- 2 Onoken
- 3 Orangestar
- 4 Otokaze
- 5 Outsider
- 6 ONE
- 7 O3ohn
- 8 On.U
- 9 otetsu
- 10 OLDE WORLDE
- 11 Olltii
- 12 OneSun
- 13 Okasian
- 14 Optical Eyez XL
- 15 Oki
- 16 Odee
- 17 osterreich
- 18 O!Gon
- 19 Owen Ovadoz
- 20 One Up (원업)
- 21 One Life
- 22 One
- 23 OFA
- 24 Owol
- 25 Ohwon Lee (진짜사나이)
- 26 OVER ARM THROW
- 27 OLFA ASTRA
- 28 OVAN
- 29 O.S.T
- 30 OTHANKQ