During this time he represented the Thai national team at schoolboy level as well as being on the books of London-based club Crystal Palace.

The young forward joined Thai Premier League side BEC Tero Sasana in 2006 aged 21 and played for the club until 2008 made totally 65 appearances scored 22 goals and won the 2008 Striker of the Year award.

Later in the first season with the Belgian club, he was moved back to Thailand and played for Thai Premier League champions Muangthong United on a loan deal.

Teeratep first came to the fore in the King's Cup in 2005 and has been a squad regular since, only being rested when called up to represent the nation in Olympic qualifying matches or in SEA Games.

In the final of the 2005 SEA Games match against Vietnam, he scored a hat-trick and helped Thailand claim the gold medal for the 7th consecutive time.

Football Association of Thailand held a retirement farewell match on 14 December 2022, in honor of Teerathep, who has been a member of the Thai national team since he was 14 years old and has played for them at every level.

[12] His performance in the first half, which lasted 30 minutes, resulted in a 1–0 loss for the Thai national football team versus the Chinese Taipei squad.