He drove in the AAA and USACChampionship Car series, racing in the 1950 and 1952-1962 seasons with 33 starts. He raced in ten Indianapolis 500 races, in each year but 1955 and 1958. His best finish at Indy was tenth in 1957, although he finished eleventh three times. He finished in the Top 10 nine times, with his best finish in second position in 1956 at Langhorne Speedway.
The Indianapolis 500 was part of the FIA World Championship from 1950 through 1960. Drivers competing at Indy during those years were credited with World Championship points and participation. Gene Hartley participated in 8 World Championship races, with a best finish of tenth.