The 2009 American Le Mans Series season was the 39th season for the IMSA GT Championship, with it being the eleventh season with the American Le Mans Series moniker. It began on March 21, 2009, and ended on October 10, 2009 after ten events. The series was composed of Le Mans Prototypes (LMP) and Grand Tourer (GT) race cars divided into four classes: LMP1, LMP2, GT1, and GT2. A fifth category, known as the Challenge class, was also added for select races and featured Porsche 997 GT3 Cup cars from the IMSA GT3 Cup Challenge. 2009 was also the final year for GT1, with Corvette Racing abandoning the class after Long Beach and switching over to much more competitive GT2 (renamed GT) class.