The Mazda 717C was a prototype racing car built by Mazdaspeed for the 24 hours of Le Mans auto race. It replaced the RX-7 racing car in 1983 and was replaced by the 727 the next year. It used a 2-rotor 13B Wankel engine, similar to the production engine in the Mazda RX-7.

Two 717s were entered at Le Mans in 1983, finishing twelfth and eighteenth and claiming the C Junior class victory.