| Coureur | Nat | Geb. / Overl. | Cm / Kg | Zeges | Dit jaar |
|---|---|---|---|---|---|
| Yosandy Darmawan Oetomo | INA | 2000-04-26 | ??cm / ??kg | 0 | 0 |
| Mario Officio | ITA | 1938-08-05 | ??cm / ??kg | 0 | 0 |
| Takahiko Ogato | JPN | 1998-12-05 | ??cm / ??kg | 0 | 0 |
| Domenico Oggero | ITA | ??cm / ??kg | 0 | 0 | |
| Ben Ogle | AUS | ??cm / ??kg | 0 | 0 | |
| Giuseppe Ogna | ITA | 1933-11-05 | ??cm / ??kg | 0 | 0 |
| Giovanni Ogulin | ITA | ??cm / ??kg | 0 | 0 | |
| Je-Seok Oh | KOR | 1997-09-18 | ??cm / ??kg | 0 | 0 |
| Taehee Oh | KOR | 1993-08-18 | ??cm / ??kg | 0 | 0 |
| Henry Ohayon | ISR | 1934-06-17 - 2023-10-27 | ??cm / ??kg | 0 | 0 |
| Hirostoshi Ohi | JPN | ??cm / ??kg | 0 | 0 | |
| Minoru Ohkawa | JPN | ??cm / ??kg | 0 | 0 | |
| Brian Ohlson | USA | 1957-11-27 | ??cm / ??kg | 0 | 0 |
| Manabu Ohwada | JPN | ??cm / ??kg | 0 | 0 | |
| Hiroshi Ohzono | JPN | ??cm / ??kg | 0 | 0 | |
| Justin Oien | USA | 1995-05-05 | ??cm / ??kg | 0 | 0 |
| Kazusa Oikawa | JPN | 1998-06-10 | ??cm / ??kg | 0 | 0 |
| Edward Oingerang | GUM | 1991-12-07 | ??cm / ??kg | 0 | 0 |
| Manuel Oioli | ITA | 2003-05-17 | ??cm / ??kg | 0 | 0 |
| Kazuo Oishi | JPN | 1961-03-24 | ??cm / ??kg | 0 | 0 |
| Kazuyoshi Okada | JPN | ??cm / ??kg | 0 | 0 | |
| Ander Okamika Bengoetxea | SPA | 1993-04-02 | ??cm / ??kg | 0 | 0 |
| Katsuya Okamoto | JPN | 2002-06-10 | ??cm / ??kg | 0 | 0 |
| Tomas Okrouhlicky | CZE | 1985-11-04 | ??cm / ??kg | 0 | 0 |
| Daniel Okrucinski | POL | 1980-03-31 | ??cm / ??kg | 0 | 0 |
| Hiroshije Okubo | JPN | ??cm / ??kg | 0 | 0 | |
| Jin Okubo | JPN | 1988-10-08 | ??cm / ??kg | 0 | 0 |
| Shouji Okuizumi | JPN | ??cm / ??kg | 0 | 0 | |
| Peio Olaberria Arruabarren | SPA | 1994-09-28 | ??cm / ??kg | 0 | 0 |
| Gabriel Olaneta | SPA | ??cm / ??kg | 0 | 0 | |
| Jaypee Olarte | PHI | 1999-08-16 | ??cm / ??kg | 0 | 0 |
| Gérard Olbe | FRA | 1948-02-04 | ??cm / ??kg | 0 | 0 |
| Karl Olböter | DUI | ??cm / ??kg | 0 | 0 | |
| Mario Oldani | ITA | ??cm / ??kg | 0 | 0 | |
| Peter Olde Dubbelink | NED | 1980-01-07 | ??cm / ??kg | 0 | 0 |
| Tom Oldfield | GBR | ??cm / ??kg | 0 | 0 | |
| Henrik Oldin | ZWE | 1975-12-03 | ??cm / ??kg | 0 | 0 |
| Federico Olei | SMR | 1996-08-03 | ??cm / ??kg | 0 | 0 |
| Peter Olejniczak | USA | 1990-06-28 | ??cm / ??kg | 0 | 0 |
| Michael Olejnik | POL | 1980-05-09 | ??cm / ??kg | 0 | 0 |
| Tomasz Olejnik | POL | 1985-05-07 | ??cm / ??kg | 0 | 0 |
| Einar Olesen | DEN | 1908-08-19 | ??cm / ??kg | 0 | 0 |
| Michael (Mike) Olheiser | USA | 1975-01-23 | ??cm / ??kg | 0 | 0 |
| Bob Olieslagers | NED | 1997-03-17 | ??cm / ??kg | 0 | 0 |
| Marco Oliosi | ITA | 2004-05-11 | ??cm / ??kg | 0 | 0 |
| Evan Oliphant | GBR | 1982-01-08 | ??cm / ??kg | 0 | 0 |
| Cesar Oliva | CHI | 1984-05-25 | ??cm / ??kg | 0 | 0 |
| Dario Oliva | ARG | ??cm / ??kg | 0 | 0 | |
| Ramon Olivares | SPA | ??cm / ??kg | 0 | 0 | |
| Oliveira | BRA | ??cm / ??kg | 0 | 0 |