| Name | Roles |
|---|
| Ordenneau, Vincent | Performer |
| Order, Jeff | Producer |
| Ordinas, David | Performer |
| Ordinola, Cesar | Performer (2) |
| Ordóñez, Jaime | Performer |
| Orea, Guillermo | Performer (2) |
| Oreily, Alan | Performer |
| Orella, Francesc | Performer |
| Oremus, Stephen | Orchestrations (4), Conductor (6), Music_Director (3), Vocal_Arrangements (2), Producer, Performer |
| Oren, Dalia | Performer |
| Orenstein, Debbie | Music, Lyrics, Performer |
| Orenstein, Harriet | Performer |
| Orenstein, John | Music, Lyrics, Performer |
| Oreskes, Daniel | Performer |
| Orezzoli, Héctor | Book (2) |
| Orfaly, Alexander | Performer (4) |
| Orfeh | Performer (7) |
| Orfeo, Camerata | Performer |
| Orfgen, Samy | Performer |
| Orgambide, Pedro | Lyrics, Book |
| Oria, Elena | Translation |
| Oribemanolo, Alejandro | Lyrics |
| Orich, Steve | Orchestrations (8), Conductor (2) |
| Orich, Steven | Orchestrations (3), Conductor |
| Oriez, Horacio | Performer (2) |
| Original Soul Singers, The | Performer (2) |
| Orihuela, Antonio | Performer |
| Orin, Renée | Performer (2) |
| Oristrell, Joaquim | Book |
| Oritz, Marlyn | Performer |
| Orive, Alejandro | Lyrics (2), Book (2), Translation |
| Orkin, Giselle | Performer |
| Orkin, Harvey | Book |
| Orland, Michael | Music_Director, Producer |
| Orlando Pops Orchestra | Performer (12) |
| Orlando, Pam | Performer |
| Orlando, Tony | Producer, Performer |
| Orlane | Performer |
| Orlob, Harold | Music |
| Orloff, Gene | Conductor |
| Orloff, Penny | Performer |
| Orlova, Olga | Performer |
| Ormandy, Eugene | Conductor (3) |
| Ormiston, Linda | Performer (2) |
| Ormsby, Lee | Performer |
| Örn, Ivar | Performer |
| Orna | Performer |
| Ornadel, Cyril | Music (5), Conductor (18), Music_Director (5), Producer (12), Performer |
| Ornest, Jiří | Performer |
| Ornolfsdottir, Alfrud Kristjansson | Performer |
