Nigel Mansell won the South African Grand Prix 1985 at Kyalami on 19 October 1985, starting from pole position. Keke Rosberg finished second for Williams, with Alain Prost completing the podium for McLaren.
| Pos | Grid | Driver | Team | Laps | Time / Status | Pts | FL |
|---|---|---|---|---|---|---|---|
| 1 | 1 | Nigel MansellMAN | Williams | 75 | 1:28:22.866 | 9 | |
| 2 | 3 | Keke RosbergROS | Williams | 75 | +7.572 | 6 | |
| 3 | 9 | Alain ProstPRO | McLaren | 74 | +1 Lap | 4 | |
| 4 | 16 | Stefan JohanssonJOH | Ferrari | 74 | +1 Lap | 3 | |
| 5 | 11 | Gerhard BergerBER | Arrows | 74 | +1 Lap | 2 | |
| 6 | 10 | Thierry BoutsenBOU | Arrows | 74 | +1 Lap | 1 | |
| 7 | 17 | Martin BrundleBRU | Tyrrell | 73 | +2 Laps | 0 | |
| R | 6 | Elio de AngelisDEA | Team Lotus | 52 | Engine | 0 | |
| R | 20 | Pierluigi MartiniMAR | Minardi | 45 | Radiator | 0 | |
| R | 8 | Niki LaudaLAU | McLaren | 37 | Turbo | 0 | |
| R | 19 | Philippe StreiffSTR | Tyrrell | 16 | Accident | 0 | |
| R | 4 | Ayrton SennaSEN | Team Lotus | 8 | Engine | 0 | |
| R | 15 | Michele AlboretoALB | Ferrari | 8 | Turbo | 0 | |
| R | 2 | Nelson PiquetPIQ | Brabham | 6 | Engine | 0 | |
| R | 13 | Piercarlo GhinzaniGHI | Toleman | 4 | Engine | 0 | |
| R | 7 | Teo FabiFAB | Toleman | 3 | Engine | 0 | |
| R | 5 | Marc SurerSUR | Brabham | 3 | Engine | 0 | |
| R | 21 | Huub RothengatterROT | Osella | 1 | Electrical | 0 | |
| R | 12 | Riccardo PatresePAT | Alfa Romeo | 0 | Accident | 0 | |
| R | 14 | Eddie CheeverCHE | Alfa Romeo | 0 | Accident | 0 | |
| W | 18 | Alan JonesJON | Lola | 0 | Driver unwell | 0 |