There was a cord around the star's neck and other parts of his body and it has been suggested that he took his own life.
Carradine was in Thailand working on his latest film, Stretch, his personal manager Chuck Binder has revealed.
Police in Bangkok said that Carradine's dead body had been discovered in a suite at the 5-star Swissotel Nai Lert Park hotel.
Thai newspaper The Nation has reported that police there believe that Carradine had committed suicide, and noted that their investigations so far have suggested that the actor hanged himself.
Carradine was most famous for his role as Kwai Chang Caine in the 1970s cult television series Kung Fu.
Carradine received both Emmy and Golden Globe nominations for his part in the series.
Carradine is survived by his wife, Annie Bierman, and three children.
Tributes are pouring in for Carradine who was a well-respected star, who had also been a musician, singer-songwriter and painter.
