O
- Oak Ridge Boys
- Oasis
- Hugh O'Brian
- Tim O'Brien
- O'Bryan
- Ric Ocasek
- Ocean
- Billy Ocean
- Phil Ochs
- Helen O'Connell
- Carroll O'Connor
- Sinead O'Connor
- Johnny October
- Ray O'Daniel
- Alan O'day
- Pat O'Day
- Kenny O'Dell
- Odyssey
- Offspring
- Lee Ofman And Gridnitz
- The Ohio Express
- Ohio Players
- Ohio Untouchables
- Oingo Boingo
- Jamie O'Hara
- The O'Jays
- The O'Kanes
- The O'Kaysions
- Danny O'Keefe
- The Oklahoma Boys
- Mike Oldfield
- Oliver
- David Oliver
- Sy Oliver And His Orchestra
- Ollie And Jerry
- Ollie And The Nightingales (60's Funk)
- Olympic Runners
- The Olympics
- Dwayne Omarr
- Michael Omartian
- O.M.D. (Orchestral Manoeuvres In The Dark)
- Tony Omerzo
- Alexander O'Neal
- Jamie O'Neal
- Jeannine O'Neal
- One 2 Many
- 100 Proof Aged In Soul (One Hundred Proof Aged In Soul)
- One Nation
- One Point One
- 112 (One-Twelve)
- One-Two-Three
- One Way
- Yoko Ono
- The Opals
- Opus
- Roy Orbison
- Orbit
- The Original Caste
- Original Casuals
- The Original Five Blind Boys
- Original Texas Playboys
- The Originals
- The Orioles
- Orion
- Tony Orlando
- The Orlandos
- Orleans
- The Orlons
- Orpheus
- Benjamin Orr
- Robert Ellis Orrall
- Orrall And Wright
- Frank Ortega Trio
- Nix Osborn And The Rounders
- The Osborne Brothers
- Osborne And Giles
- Jeffrey Osborne
- Ozzy Osbourne
- Osibisa
- Lee Oskar
- K. T. Oslin
- Donny Osmond
- Marie Osmond
- The Osmonds
- Walter Ostanek
- Gilbert O'Sullivan
- Otis And Carla
- Clyde Otis And His Orchestra
- The Johnny Otis Show
- O-Town
- The Outfield
- The Outlaws
- The Outsiders
- The Ovations
- Paul Overstreet
- Tommy Overstreet
- Reg Owen
- Bonnie Owens
- Owens Brothers
- Buck Owens
- Donnie Owens
- Vernon Oxford
- OXO
- Ozark Mountain Daredevils