Geoff Brabham (born 20 March 1952) is an Australian racing driver. He is the son of three-time Formula One World Champion Jack Brabham. Brabham spent the majority of his racing career in the United States. He raced successfully in CART early in his career. In ten appearances in the Indianapolis 500, with a best result of fourth in 1983. His greatest source of success was in various forms of sports cars, winning four IMSA GTP titles (1988 - 1991) when racing for Nissan, and one Can-Am championship (1981). He also won the 1993 Le Mans 24 hours, took two race victories in the International Race of Champions (1992 and 1993), both at Michigan. Brabham made his only NASCAR Winston Cup Series start at the first ever Brickyard 400 at Indianapolis in 1994, driving for Michael Kranefuss. Brabham crashed in the second half of the race. He has two younger brothers; Gary and David. Brabham teamed with David to win the 1997 Bathurst 1000 in a BMW. Although the most successful of the second generation of racing Brabhams, unlike his siblings he did not compete in World Championship Formula One.
Brabham dabbled in V8 Supercar drives in his native Australia throughout his career. He is still one of the few drivers to win his first race, Sandown 500 in 1993. He started eleven races for one victory.
Brabham now works for BMW Group Australia as a driver trainer at many different events around the country teaching others to drive safer and smarter, including teaching drivers to race for BMW supported celebrity races at the Australian Grand Prix. His son Matthew Brabham is also following in the family interest and is a very successful Kart racer.