500cc Classification
| Pos | Rider | Manufacturer | Time/Retired | Points |
|---|---|---|---|---|
| 1 | Wayne Rainey | Yamaha | 46:08.566 | 20 |
| 2 | Kevin Schwantz | Suzuki | +2.946 | 17 |
| 3 | Mick Doohan | Honda | +6.066 | 15 |
| 4 | Wayne Gardner | Honda | +23.218 | 13 |
| 5 | Niall Mackenzie | Yamaha | +33.205 | 11 |
| 6 | John Kocinski | Yamaha | +37.614 | 10 |
| 7 | Juan Garriga | Yamaha | +39.280 | 9 |
| 8 | Didier de Radiguès | Suzuki | +39.566 | 8 |
| 9 | Doug Chandler | Yamaha | +52.121 | 7 |
| 10 | Jean Philippe Ruggia | Yamaha | +1:15.609 | 6 |
| 11 | Eddie Laycock | Yamaha | +1 Lap | 5 |
| 12 | Marco Papa | Cagiva | +1 Lap | 4 |
| 13 | Cees Doorakkers | Honda | +1 Lap | 3 |
| 14 | Michael Rudroff | Honda | +1 Lap | 2 |
| 15 | Hans Becker | Yamaha | +1 Lap | 1 |
| 16 | Josef Doppler | Yamaha | +1 Lap | |
| 17 | Romolo Balbi | Honda | +1 Lap | |
| 18 | Andreas Leuthe | Suzuki | +2 Laps | |
| 19 | Helmut Schutz | Honda | +2 Laps | |
| Ret | Sito Pons | Honda | Retirement | |
| Ret | Michele Valdo | Paton | Retirement | |
| Ret | Eddie Lawson | Cagiva | Retirement | |
| Ret | Adrien Morillas | Yamaha | Retirement |
| Previous race: 1991 British Grand Prix |
FIM Grand Prix World Championship 1991 season |
Next race: 1991 Czechoslovakian Grand Prix |
| Previous race: 1987 San Marino Grand Prix |
San Marino Grand Prix | Next race: 1993 San Marino Grand Prix |
Read more about this topic: 1991 San Marino Motorcycle Grand Prix