2009 in Thai football

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.

Promotion and relegation (pre-season)
Teams promoted to Thai Premier League 2009
 * Muangthong United
 * Sriracha
 * Rajnavy Rayong

Teams relegated from Thailand Premier League 2008
 * Customs Department Phetchaburi
 * Royal Thai Army
 * Bangkok Bank (withdraw)

Teams promoted to Thai Division 1 League 2009
 * Prachinburi
 * Songkhla
 * Sisaket

Teams relegated from Thailand Division 1 League 2008
 * Phitsanulok
 * Raj-Vithi

Diary of the season

 * 1 March 2009: Chonburi won the Kor Royal Cup beating PEA 1–0 at Suphachalasai Stadium.
 * 7 March 2009: The first Thai Premier League matches of the season are played.
 * 18 November 2009: Thailand lost to Singapore at home stadium for first time in 34 years, after they lost 0–1 in 2011 AFC Asian Cup qualification.
 * 23 October 2009: The Thai FA Cup is won by Thai Port on penalties against BEC Tero Sasana after a 1–1 draw at Suphachalasai Stadium.

Retirements

 * 18 October 2009: Tawan Sripan, 37-year-old BEC Tero Sasana midfielder.

Asian Cup qualifiers
Thailand is currently in Group E of the 2011 AFC Asian Cup qualification process.