1991 Formula One season Drivers and constructors Drivers and constructors

| Entrant | Constructor_ | Chassis | Engine | Tyre | Driver | Rounds |
|---|---|---|---|---|---|---|
| Honda Marlboro McLaren | McLaren - Honda | MP4/6 | Honda RA121E 3.5 V12 | G | Ayrton Senna | All |
| Honda Marlboro McLaren | McLaren - Honda | MP4/6 | Honda RA121E 3.5 V12 | G | Gerhard Berger | All |
| Braun Tyrrell Honda | Tyrrell - Honda | 020 | Honda RA101E 3.5 V10 | P | Satoru Nakajima | All |
| Braun Tyrrell Honda | Tyrrell - Honda | 020 | Honda RA101E 3.5 V10 | P | Stefano Modena | All |
| Canon Williams Team | Williams - Renault | FW14 | Renault RS3 3.5 V10 | G | Nigel Mansell | All |
| Canon Williams Team | Williams - Renault | FW14 | Renault RS3 3.5 V10 | G | Riccardo Patrese | All |