Peter Kenneth Gethin (21 February 1940 in Ewell, Surrey, United Kingdom – 5 December 2011) was a British racing driver from England. He participated in 31 World Championship Formula One Grands Prix, debuting on 21 June 1970. He won the 1971 Italian Grand Prix in the fastest average speed in Formula One history, but this was his only podium finish. Gethin also participated in numerous non-Championship Formula One races, winning the 1971 World Championship Victory Race and the 1973 Race of Champions.
Gethin also raced for Team McLaren in the 1970 Canadian-American Challenge Cup series, driving the McLaren M8D that had been driven by Dan Gurney in the first three races of the season. Gethin won one race and finished third in the 1970 championship. In 1974 Gethin won the Tasman Series, a Formula 5000 series held in Australia and New Zealand. Gethin drove a Chevron B24 Chevrolet. Gethin later ran a Formula 3000 team.