2003 Rio de Janeiro motorcycle Grand Prix
The 2003 Rio de Janeiro motorcycle Grand Prix was the twelfth round of the 2003 MotoGP Championship. It took place on the weekend of 18-20 September 2003 at Autódromo Internacional Nelson Piquet.
The 125cc race marked the first Grand Prix motorcycle racing victory for a young Jorge Lorenzo.250 cc classification
125 cc classification
Championship standings after the race (motoGP)
Below are the standings for the top five riders and constructors after round twelve has concluded.
;Riders' Championship standings
| Rider | Points |
| 1 |  Valentino Rossi | 262 |
| 2 |  Sete Gibernau | 211 |
| 3 | Max Biaggi | 174 |
| 4 | Loris Capirossi | 123 |
| 5 |  Troy Bayliss | 112 |
;Constructors' Championship standings
| Constructor | Points |
| 1 |  Honda | 295 |
| 2 | Ducati | 171 |
| 3 | Yamaha | 132 |
| 4 | Aprilia | 63 |
| 5 |  / Proton Team KR | 27 |
- Note: Only the top five positions are included for both sets of standings.
