John Mahler (born November 16, 1936, Alpha, Iowa), is a former open wheel race car driver in the USAC and CART Championship Car series. He raced in the 1970-1973 and 1976-1981 seasons, with 39 combined career starts, including the 1972 and 1977-1979 Indianapolis 500. He finished in the top ten 6 times, with his best finish in 6th position in 1970 at the Indianapolis Raceway Park road course. Mahler currently owns and operates Classic Concrete Designs in Kansas City, Missouri.