| KTM Red Bull KTM #1 Arnaud Vincent (FRA) #10 Roberto Locatelli (ITA) |
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Junior Team Honda #3 Daniel Pedrosa (SPA) |
| Safilo Oxydo Race
- LCR Aprilia #4 Lucio Cecchinello (ITA) #27 Casey Stoner (AUS) |
Matteoni Racing Aprilia #6 Mirko Giansanti (ITA) #58 Marco Simoncelli (ITA) |
| Abruzzo Aprilia #7 Stefano Perugini (ITA) #11 Max Sabbatani (ITA) |
Ajo Motorsport Honda #8 Masao Azuma (JPN) #36 Mika Kallio (FIN) |
| Elit Grand Prix Honda #12 Thomas Lüthi (SUI) |
Seedorf Racing Aprilia #14 Chris Martin (GBR) #19 Alvaro Bautista (SPA) |
| Racing World Aprilia #15 Alex de Angelis (RSM) #23 Gino Borsoi (ITA) |
Imola Circuit Exalt
Cycle Race Aprilia #17 Steve Jenkner (GER) #79 Gabor Talmacsi (HUN) |
| Metasystem Racing
Service Honda #20 Peter Lenart (HUN) #21 Leon Camier (GBR) |
Master - Aspar Team Aprilia #22 Pablo Nieto (SPA) #80 Hector Barbera (SPA) |
| Team Scot Honda #24 Simone Corsi (ITA) #34 Andrea Dovizioso (ITA) |
Team Hungary Honda #25 Imre Toth (HUN) |
| Caja Madrid Derbi
Racing Derbi #26 Emilio Alzamora (SPA) #48 Jorge Lorenzo (SPA) |
Semprucci Malaguti Malaguti #31 Julian Simo (SPA) #32 Fabrizio Lai (ITA) |
| Gilera Racing Gilera #33 Stefano Bianco (ITA) |
Sterigalda Racing Aprilia #41 Youichi Ui (JPN) #42 Gioele Pellino (ITA) |
| Free Soul Racing Team Aprilia #63 Mike di Miglio (FRA) |
| Fortuna Honda Honda RSW 250 #3 Roberto Rolfo (ITA) |
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Junior Team Honda RSW 250 #5 Sebastian Porto (ARG) |
| Honda BQR Honda RS 250 R #6 Alex Debon (SPA) #34 Eric Bataille (FRA) |
Safilo Oxydo Race
- LCR Aprilia RSW 250 #7 Randy de Puniet (FRA) |
| Yamaha Kurz Yamaha TZ 250 #8 Naoki Matsudo (JPN) #13 Jaroslav Hules (CZE) |
Equipe de France -
Scrab GP Aprilia RS 250 #9 Hugo Marchand (FRA) #36 Erwan Nigon (FRA) |
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- Repsol YPF Aprilia RSW 250 #10 Fonsi Nieto (SPA) #24 Toni Elias (SPA) |
Team Aspar Junior Aprilia RS 250 #11 Joan Olive (SPA) #33 Hector Faubel (SPA) |
| Azzura Aprilia RSW 250 #14 Anthony West (AUS) #16 Johan Stigefelt (SWE) |
Kiefer Castrol Honda Honda RS 250 R #15 Christian Gemmel (GER) |
| Arie Molenaar Honda RS 250 R #18 Henk van de Lagemaat (NED) #98 Katja Poensgen (GER) |
Campetella Racing Aprilia RS 250 #21 Franco Battaini (ITA) #50 Sylvain Guintoli (FRA) |
| Team Hungary Honda RS 250 #25 Gabor Rizmayer (HUN) |
Matteoni Racing Aprilia RS 250 #26 Alex Baldolini (ITA) |
| Aprilia Germany Aprilia RS 250 #28 Dirk Heidolf (GER) #57 Chaz Davies (GBR) |
MS Aprilia Racing Aprilia RSW 250 #54 Manuel Poggiali (RSM) |
| Elit Grand Prix Honda RS 250 R #96 Jakub Smrz (CZE) |
| Camel Pramac Pons Honda RC211V + Michelin #2 Max Biaggi (ITA) #11 Tohru Ukawa (JPN) |
Gauloises Yamaha Team Yamaha YZR-M1 + Michelin #4 Alex Barros (BRA) #19 Olivier Jacque (FRA) |
| Pramac Honda Honda RC211V + Bridgestone #6 Makoto Tamada (JPN) |
Fortuna Yamaha Team Yamaha YZR-M1 + Michelin #7 Carlos Checa (SPA) #33 Marco Melandri (ITA) |
| Fuchs Kawasaki Racing
Team Kawasaki "Ninja" ZX-RR + Dunlop #8 Garry McCoy (AUS) #88 Andrew Pitt (AUS) |
Proton Team KR Proton KR Mk3/MX1 + Bridgestone #9 Nobuatsu Aoki (JPN) #99 Jeremy McWilliams (UK) |
| Suzuki Grand Prix
Team Suzuki GSV-R + Michelin #10 Kenny Roberts (USA) #21 John Hopkins (USA) |
Ducati Marlboro Team Ducati Desmosedici + Michelin #12 Troy Bayliss (AUS) #65 Loris Capirossi (ITA) |
| Telefonica Movistar
Honda Honda RC211V + Michelin #15 Sete Gibernau (SPA) #23 Ryuichi Kiyonari (JPN) #74 Daijiro Kato (JPN) |
WCM Harris WCM + Dunlop #35 Chris Burns (GBR) #?? Jose Luis Cardoso (SPA) |
| Alice Aprilia Racing Aprilia RS³ + Michelin #41 Noriyuki Haga (JPN) #45 Colin Edwards (USA) |
Repsol Honda Honda RC211V + Michelin #46 Valentino Rossi (ITA) #69 Nickey Hayden (USA) |
| Yamaha D'Antin Yamaha YZR-M1 + Michelin #56 Shinya Nakano (JPN) |