1909 AAA Championship Car season

The 1909 AAA Championship Car season consisted of 24 races, beginning in Portland, Oregon on June 12 and concluding with a point-to-point race from Los Angeles, California to Phoenix, Arizona on November 6. There were three events sanctioned by the Automobile Club of America in Lowell, Massachusetts. The de facto National Champion as poled by the American automobile journal Motor Age was Bert Dingley. Points were not awarded by the AAA Contest Board during the 1909 season. Champions of the day were decided by Chris G. Sinsabaugh, an editor at Motor Age, based on merit and on track performance. The points table was created retroactively in 1927 keeping Dingley as champion. In 1951 the championship standings were reworked, stripping the traditional champion of his title and giving it to George Robertson. All championship results should be considered unofficial.

Schedule and results
* William Bourque and his riding mechanic Harry Holcomb fatally injured on lap 58

** Race halted at 235 miles due to track breaking up. AAA report states that race was halted at 245 miles. Claude Kellem, Charles Merz's riding mechanic, was killed. Merz's car broke through the fence and crashed into spectators fatally injuring Howard H. Jolliff and James West.

*** Event sanctioned by Automobile Club of America, 301–450, 231–300 & 161–230 run simultaneously.

**** All classes run simultaneously.

Leading National Championship standings
* Bert Dingley was poled as national champion in 1909 and held his championship when points were applied in 1927. These are the final standing as of 1951 after AAA revised the championship trail for 1909. The earliest know occurrence of George Robertson holding the title was in the 1952 Indianapolis 500 program.

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. Points were awarded as follows.