| Coureur | Nat | Geb. / Overl. | Cm / Kg | Zeges | Dit jaar |
|---|---|---|---|---|---|
| Folkert Oostra | NED | 1989-09-28 | ??cm / ??kg | 0 | 0 |
| Gustave Op 't Eynde | BEL | 1928-08-18 | ??cm / ??kg | 0 | 0 |
| Fritz Opel | DUI | 1875-03-31 | ??cm / ??kg | 0 | 0 |
| Ludwig Opel | DUI | ??cm / ??kg | 0 | 0 | |
| Sidney Opperman | AUS | ??cm / ??kg | 0 | 0 | |
| Osvaldo Oprandi | ITA | ??cm / ??kg | 0 | 0 | |
| Ad Oprins | NED | 1950-08-25 | ??cm / ??kg | 0 | 0 |
| Jules Oprins | BEL | 1916-02-16 | ??cm / ??kg | 0 | 0 |
| Frans Oprinus | BEL | ??cm / ??kg | 0 | 0 | |
| Oleg Opryshko | UKR | 1986-07-16 | ??cm / ??kg | 0 | 0 |
| Allan Oras | EST | 1975-12-20 | ??cm / ??kg | 0 | 0 |
| Paul Orban | HUN | 1940-10-26 | ??cm / ??kg | 0 | 0 |
| Haritz Orbe Urrutia | SPA | 1991-07-18 | ??cm / ??kg | 0 | 0 |
| José Orbegozo | SPA | ??cm / ??kg | 0 | 0 | |
| Clément Orceau | FRA | 1995-07-01 | ??cm / ??kg | 0 | 0 |
| Toby Orchard | AUS | 1996-05-20 | ??cm / ??kg | 0 | 0 |
| Efe Orcun | TUR | 2004-12-11 | ??cm / ??kg | 0 | 0 |
| Fernando Ordóñez Citoula | SPA | 1977-07-07 | ??cm / ??kg | 0 | 0 |
| Volker Ordowski | DUI | 1973-11-09 | 180cm / 70kg | 0 | 0 |
| José Orduna | SPA | ??cm / ??kg | 0 | 0 | |
| Thomas Oredsson | DEN | 1980-02-02 | ??cm / ??kg | 0 | 0 |
| Lars Oreel | NED | 1999-08-10 | ??cm / ??kg | 0 | 0 |
| Antonio Orefice | ITA | ??cm / ??kg | 0 | 0 | |
| Dave Orford | GBR | ??cm / ??kg | 0 | 0 | |
| Carlo Oria | ITA | 1908-08-03 | ??cm / ??kg | 0 | 0 |
| Celestino Oriani | ITA | 1933-07-01 - 1993-12-22 | ??cm / ??kg | 0 | 0 |
| Marcello Oriboni | ITA | ??cm / ??kg | 0 | 0 | |
| Maurice Origne | FRA | 1915-03-22 | ??cm / ??kg | 0 | 0 |
| Robin Orins | BEL | 2002-03-06 | 190cm / ??kg | 0 | 0 |
| Alessandro Orioli | ITA | 1901-05-19 | ??cm / ??kg | 0 | 0 |
| Giorgio Orizio | ITA | 1982-02-03 | ??cm / ??kg | 0 | 0 |
| Fernando Orjuela Gutierrez | COL | 1991-11-04 | ??cm / ??kg | 0 | 0 |
| Dante Orlandi | ITA | 1934-04-23 | ??cm / ??kg | 0 | 0 |
| Mario Orlandi | ITA | ??cm / ??kg | 0 | 0 | |
| Massimo Orlandi | ITA | 1998-12-03 | ??cm / ??kg | 0 | 0 |
| Mario Orlandi (1957) | ITA | 1957-04-23 | ??cm / ??kg | 0 | 0 |
| C. Orlandini | ITA | ??cm / ??kg | 0 | 0 | |
| Alexandre Orlando | POR | ??cm / ??kg | 0 | 0 | |
| Fabrizio Orlando | ITA | 1963-12-13 | ??cm / ??kg | 0 | 0 |
| Gaston Orlans | BEL | 1929-07-04 | ??cm / ??kg | 0 | 0 |
| Boris Orlhac | FRA | 1991-11-21 | ??cm / ??kg | 0 | 0 |
| Jokin Ormaetxea Badiola | SPA | 1980-05-26 - 2004-10-23 | ??cm / ??kg | 0 | 0 |
| William Anthony Ormston | GBR | ??cm / ??kg | 0 | 0 | |
| Victor Orole | BEL | ??cm / ??kg | 0 | 0 | |
| Emerson Oronte | USA | 1990-01-29 | ??cm / ??kg | 0 | 0 |
| Gergö Orosz | HUN | 1999-04-28 | ??cm / ??kg | 0 | 0 |
| Francisco J. Orozco | COL | 1972-03-15 | ??cm / ??kg | 0 | 0 |
| Robert Orr | GBR | 1980-10-01 | ??cm / ??kg | 0 | 0 |
| Davide Orrico | ITA | 1990-02-17 | ??cm / ??kg | 0 | 0 |
| Orsini | FRA | ??cm / ??kg | 0 | 0 |