The 2009 season of competitive football in Thailand.
The season began on 7 March 2009 for the Thai Premier League and 21 March 2009 for the Division 1 League.
The Division 1 season ended on 17 October 2009, and the Thai Premier League season ended on 18 October 2009.
Teams promoted to Thai Premier League 2009 Teams relegated from Thailand Premier League 2008 Teams promoted to Thai Division 1 League 2009 Teams relegated from Thailand Division 1 League 2008 Thailand is currently in Group E of the 2011 AFC Asian Cup qualification process.