The 1991 British Touring Car Championship (BTCC) Round 9 was a Touring Car race that was held on 26 August 1991 at the Silverstone Circuit in Northamptonshire, England. The race was contested over one eight-lap sprint and one sixteen-lap feature race and was the ninth round of the 1991 British Touring Car Championship. The feature race also awarded double points.
Heading into the meeting, Roy Cop was leading the Overall and Manufacturer Drivers' Championship by fifty-four points from Michael Sneath. Kaliber ICS Team Toyota was leading the Manufacturer's Team Championship by thirty-three points from Nissan Janspeed Racing. In the Independent Driver's Championship, Mike Bell lead Kris Simton by thirty points. However it was Simton's Auto Trader Techspeed Team which lead the Independent Team's Championship over ACE Motorsport by forty-two points.
Nine drivers representing six teams entered the race. Nissan Janspeed Racing, Kaliber ICS Team Toyota and John Maguire Racing Team entered two cars and ACE Motorsport, BMW Team Listerine and Autotrader Techspeed entered single cars.
Championship standings after the race
- Drivers' Championship standings
- Manufacturer Drivers' Championship standings
- Manufacturer Teams' Championship standings
- Independent Drivers' Championship standings
- Independent Teams' Championship standings