1999 Rio de Janeiro motorcycle Grand Prix
The 1999 Rio de Janeiro motorcycle Grand Prix was the fifteenth round of the 1999 Grand Prix motorcycle racing season. It took place on 24 October 1999 at the Autódromo Internacional Nelson Piquet.250 cc classification
125 cc classification
Championship standings after the race (500cc)
Below are the standings for the top five riders and constructors after round fifteen has concluded.
;Riders' Championship standings
;Constructors' Championship standings
| Constructor | Points |
| 1 |  Honda | 327 |
| 2 | Yamaha | 260 |
| 3 | Suzuki | 206 |
| 4 |  Aprilia | 99 |
| 5 |  MuZ Weber | 58 |
- Note: Only the top five positions are included for both sets of standings.
Àlex Crivillé
Kenny Roberts Jr.