Percival Guy Tunmer (1 December 1948 – 22 June 1999) was a racing driver from South Africa. He participated in one Formula One World Championship Grand Prix, his home race in 1975, driving a Lotus 72 for a local team, Team Gunston. He finished 11th, scoring no championship points. He later found success in Formula Atlantic.

Guy Tunmer was killed in a motorcycle accident in his native South Africa in 1999.

Complete Formula One World Championship results

(key)

Year Entrant Chassis Engine 1 2 3 4 5 6 7 8 9 10 11 12 13 14 WDC Points 1975 Team Gunston Lotus 72 Cosworth V8 ARG BRA RSA
11 ESP MON BEL SWE NED FRA GBR GER AUT ITA USA NC 0