| The Option |
| The Options |
| The Opus |
| THE ORAL CIGARETTES |
| The Orange Girl |
| The Orange Lights |
| The Orangu-Tones |
| The Orb |
| The Orchard |
| The Orchestra |
| The Orchids |
| The Ordinaires |
| The Ordinary Boys |
| The Organ |
| The Orgels |
| The Orginal Moonmaids Plus One |
| The Orielles |
| The Original |
| The Original Blind Boys of Mississippi |
| The Original Brothers |
| The Original Carter Family |
| The Original Death Row Eastsidaz |
| The Original Five Blind Boys of Alabama |
| The Original Five Blind Boys of Mississippi |
| The Original Harmony Ridge Creekdippers |
| The Original Howlin Wolf and His Orchestra |
| The Original J.B.s |
| The Original Memphis Five |
| The Original Pied Pipers |
| The Original Prunes |
| The Original Salty Dogs |
| The Original Soul Seekers |
| The Original Soul Stirrers |
| The Original Tuxedo Jazz Orchestra |
| The Original Wildcat Jass Band |
| The Original Wolverines |
| The Originals |
| The Orioles |
| The Orlons |
| The Orphan Newsboys |
| The Orthodox Church Music Ensemble |
| The Orwells |
| The Osborne Brothers |
| The Oscar Peterson Trio |
| The Oscar Pettiford Orchestra |
| The Osmond Boys |
| The Osmond Brothers |
| The Osmonds |
| The Oster-Welker Jazz Alliance |
| The Ostprausters |
| The Othello Syndrome |
| The Other |
| The Other End |
| The Other Ones |
| The Other Tribe |
| The Other Two |
| The Others |
| The Others (Aka 22 Pistepirkko) |
| The Otherz |
| The Out Cast |
| The Out-Islanders |
| The Outback Singers |
| The Outcast |
| The Outcastkid |
| The Outcasts |
| The Outfield |
| The Outfit |
| The Outhere Brothers |
| The Outlaws |
| The Outlets |
| The Outline |
| The Outpatience |
| The Outs |
| The Outside Agency |
| The Outsiders |
| The Outtengrand Orchestra |
| The Ovations |
| The Overlanders |
| The Overslept |
| The Oversoul 13 |
| The Overtones |
| The Ovines |
| The Oxford Trinity Choir |
| The Oxydants |
| The Oyster Murders |
| The Oz |
| The Ozark Mountain Daredevils |
| The P. Raney Coalition |
| The Pablo All-Stars |
| The Pablo Collective |
| The Pacific |
| The Pacific Jazz Alliance |
| The Pack |
| The Pack A.D. |
| The Paddingtons |
| The Paddy Cakes |
| The Paganini Duo |
| The Pagans |
| The Page Cavanaugh Trio |
| The Pahinui Brothers |
