Nelson Piquet won the San Marino Grand Prix 1981 at Autodromo Enzo e Dino Ferrari on 3 May 1981, starting from P5 on the grid. Riccardo Patrese finished second for Arrows, with Carlos Reutemann completing the podium for Williams.
| Pos | Driver | Team | Grid | Pts | FL | Status |
|---|---|---|---|---|---|---|
1 | | 5 | 9 | Finished | ||
2 | | | 9 | 6 | Finished | |
3 | | | 2 | 4 | Finished | |
4 | | | 13 | 3 | Finished | |
5 | | | 6 | 2 | Finished | |
6 | | | 14 | 1 | Finished | |
7 | | | 1 | 0 | Finished | |
8 | | 3 | 0 | +1 Lap | ||
9 | | 21 | 0 | +1 Lap | ||
10 | | 7 | 0 | +2 Laps | ||
11 | | 16 | 0 | +2 Laps | ||
12 | | 8 | 0 | +2 Laps | ||
13 | | 24 | 0 | +3 Laps | ||
N | | 18 | 0 | Not classified | ||
R | | 23 | 0 | Spun off | ||
R | | 17 | 0 | Collision | ||
R | | 20 | 0 | Collision | ||
R | | 11 | 0 | Collision | ||
R | | 19 | 0 | Collision | ||
R | | 12 | 0 | Gearbox | ||
R | | 15 | 0 | Engine | ||
R | | 10 | 0 | Suspension | ||
R | | 4 | 0 | Gearbox | ||
R | | 22 | 0 | Accident | ||
F | | 0 | 0 | Did not qualify | ||
F | | 0 | 0 | Did not qualify | ||
R | | 0 | 0 | Retired | ||
F | | 0 | 0 | Did not qualify | ||
F | | 0 | 0 | Did not qualify | ||
F | | 0 | 0 | Did not qualify | ||
W | | 0 | 0 | Withdrew | ||
W | | 0 | 0 | Withdrew |