- The Operation -- The Orange Humble Band
- The Orange Man Theory -- The Orbits (Rock)
- The Orchard Presents -- The Order
- The Order of Apollyon -- The Orginal Brothers and Sisters of Love
- The Orginal Moonmaids Plus One -- The Original Canton Spirituals
- The Original Cast Of The 1955 Broadway Production -- The Original Klezmer Ensemble
- The Original Klezmer Ensemble -- The Original Playboy
- The Original Reverand Jones -- The Originator
- The Orioles -- The Orphics
- The Orphins -- The Other
- The Other 5 -- The Other People Place
- The Other Planets -- The Otis Problem
- The Otis Rush Blues Band -- The Out_Circuit