The 1918 AAA Championship Car season consisted of 16 races, beginning in Uniontown, Pennsylvania on May 16 and concluding there on September 2. There were also 3 non-championship races. AAA did not award points towards a National Championship during the 1918 season, and did not declare a National Champion.^[1]

The de facto National Champion as polled by the American automobile journal Motor Age, was Ralph Mulford. Mulford was named the champion by Chris G. Sinsabaugh, an editor at Motor Age, based upon merit and on track performance. A points table was created retroactively in 1927. At a later point, it was recognized by historians that these championship results should be considered unofficial.

The points paying system for the 1909–1915 and 1917–1919 season were retroactively applied in 1927 and revised in 1951 using the points system from 1920.