2015 Thai Division 1 League
| Season | 2015 | 
|---|---|
| Champions | Police United | 
| Promoted | Pattaya United Sukhothai BBCU  | 
| Relegated | Phichit Ayutthaya Phuket TTM Trat  | 
| Matches played | 379 | 
| Goals scored | 1,074 (2.83 per match) | 
| Top goalscorer | Tana Chanabut Felipe Ferreira (25 goals)  | 
| Biggest home win | Police United 7–0 Trat (22 April 2015)  | 
| Biggest away win | Trat 0–5 PTT Rayong (4 July 2015)  | 
| Highest scoring | Phichit 6–3 Phuket (5 July 2015)  | 
| Longest winning run | 5 games Police United  | 
| Longest unbeaten run | 14 games Police United  | 
| Longest winless run | 13 games Chiangmai  | 
| Longest losing run | 8 games Trat  | 
| Highest attendance | 7,657 Sukhothai 2–0 Thai Honda (9 December 2015)  | 
| Lowest attendance | 0 TTM 0–1 Phuket (28 October 2015)  | 
| Total attendance | 659,219 | 
| Average attendance | 1,739 | 
← 2014  2016 →   | |
2015 Thai League Division 1 (known as Yamaha League-1 for sponsorship reasons) was the 18th season of the League since its establishment in 1997. It is the feeder league for the Thai Premier League. A total of 20 teams competed in the league this season.