The Porsche 718 is an open-cockpit racing car built by Porsche between 1957 and 1962.
The 718 was a development of the successful Porsche 550A with improvements being made to the body work and suspension. The new front frame resembled the letter K if viewed from the front and this led to the car being referred to as the RSK. It had a mid-engined layout and used the 142 horsepower (106 kW) 1.5-litre Type 547/3 quad-cam engine introduced in the 550A. The car made its racing debut at the 1957 24 Hours of Le Mans driven by Umberto Maglioli and Edgar Barth. The car failed to finish the race due to an accident.
In 1958, the car finished first in class and third overall at Le Mans guided by Jean Behra and Hans Herrmann. Jean Behra also brought one of the cars home second at the Targa Florio. In 1959, the car, driven by Edgar Barth and Wolfgang Seidel, claimed overall victory at the Targa Florio. A 718 also won the European Hill Climb Championship in both 1958 and 1959.
In 1961 Masten Gregory and Bob Holbert piloted a 718/4 RS Spyder to a class win at Le Mans.