Former prime minister Samak Sundaravej died of liver cancer at 8.48am on Tuesday at Bamrungrad Hospital, his younger brother Sumitr said.
Samak, 74, was the country's 25th prime minister. As the leader of the since-disbanded People Power Party, he filled the positions of prime minister and defence minister from Jan 29, 2008 to Sept 9, 2008.
He was disqualified from the prime ministership when the Constitution Court found he breached the constitution by being an employee of a private firm while in office. Mr Samak was the popular host of a popular, politically oriented TV cooking programme Chim Pai, Bon Pai (Tasting While Grumbling) which many people thought was the epitome of the man himself.
Although the constitution allowed him to regain the prime minister's job if MPs voted him back into office, he instead chose to resign from the leadership of the People Power Party.
An independent and colourful character, the veteran politician was a former governor of Bangkok and founder of the Prachakorn Thai Party. He also held the offices of minister of the interior, minister of transport and deputy agriculture and cooperatives minister.
Samak sought treatment for liver cancer in November 2008 in Los Angeles and returned to Bangkok on January this year but made no public appearances from then on.
Samak was admitted to the intensive care unit of Bumrungrad Hospital on Monday. His relatives said he was was fully conscious and was able to talk with them.