The former Manchester United midfielder will sign a four-year contract with the Southeast Asian side and will be expected to build a squad capable of reaching the 2014 World Cup finals.
"He's agreed to become coach, he's very happy with what we've offered him," Worawi Makudi said.
"It's a four-year deal. The plan is he'll coach Thailand for the Asian Cup, the Olympics and hopefully the World Cup too."
Worawi said Robson would formally sign his contract once his accountant had proof-read the terms.
Robson, who played in three World Cups, has managed four English sides but has been without a club since quitting Sheffield United in February last year.
The 52-year-old, who was nicknamed 'Captain Marvel' as a player, becomes Thailand's ninth foreign coach since 1976 and the third ex-England international to take the job after Peter Withe and Peter Reid.
Robson will replace Reid, who parted company with the Thais on September 9 after less than a year in charge.
Reid's lucrative contract was terminated by mutual consent after his request to remain Thailand coach while serving as assistant manager at Premier League Stoke City was shot down.
Robson's first task will be to qualify for the 2011 Asian Cup in Qatar. Thailand are currently third in Group E with two points from their first two games and share the group with Iran, Singapore and Jordan.
He will also be expected to play a role in improving Thailand's fledgling professional league and developing the grassroots game across the country of 67 million people.
During his 13 years at Manchester United, Robson won two league titles, four FA Cups and the European Cup Winners' Cup. He was capped 90 times by England.
In addition to Sheffield United, he managed Middlesbrough, Bradford City, West Bromwich Albion.
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