| Season | 2009 |
|---|---|
| Champions | Muangthong United |
| Relegated | Sriracha Chula United Nakhon Pathom |
| 2010 AFC Champions League | Muangthong United |
| 2010 AFC Cup | Thai Port |
| Top goalscorer |  Anon Sangsanoi(BEC Tero Sasana) (18) |
| Biggest home win | BEC Tero Sasana 5-0 Chula United |
| Biggest away win | Rajnavy Rayong 0-3 TTM Samut Sakhon Sriracha 0-3 Thai Port Chonburi 2-5 Muangthong United TOT 1-4 BEC Tero Sasana BEC Tero Sasana 1-4 Muang Thong United Samut Songkhram 0-3 Rajnavy Rayong Osotspa Saraburi 0-3 BEC Tero Sasana Nakhon Pathom 2-5 Bangkok Glass |
| Highest scoring | Chonburi 2-5 Muangthong United Nakhon Pathom 2-5 Bangkok Glass (7) |
| Highest attendance | Muangthong United 1–1 Chonburi (16,608) (4 October 2009) |
← 2008 2010 → | |
The Thai Premier League 2009 was the thirteenth season of the Premier League since its establishment in 1996. A total of 16 teams competed in the league, with PEA FC as the defending champions.
Muang Thong United took the league championship with two games remaining, the first ever team to win the championship in their debut appearance in the top flight.
Nakhon Pathom, Sriracha and Chula United were relegated to the 1st Division.