The 1991 Belgian Grand Prix was a Formula One motor race held at the Circuit de Spa-Francorchamps on 25 August 1991. It was the eleventh race of the 1991 Formula One World Championship.

The race was won by Brazilian Ayrton Senna, driving a McLaren-Honda, after he started from pole position. His Austrian teammate Gerhard Berger finished second, with another Brazilian, Nelson Piquet, third in a Benetton-Ford. Senna's Drivers' Championship rival, Briton Nigel Mansell, retired with an electrical failure, allowing Senna to extend his lead over him to 22 points with five races remaining.

The race marked the debut of future seven-time World Champion, German Michael Schumacher, driving a Jordan-Ford. Schumacher qualified seventh, which matched the team's season-best grid position, and Schumacher outqualified veteran Andrea de Cesaris. Although he retired on the opening lap with a clutch failure, Schumacher's debut impressed the paddock. His seventh place qualifying was done in a midfield car, the Jordan 191, which he drove half a day of testing and at a track he had never raced at.