Chalong Police were originally alerted by a tourist on Sunday that a body had been spotted floating off Koh Hey, but a search by staff of the Pearl of Andaman Emergency Centre failed to find the corpse before dark.
The search resumed yesterday and was successful around 4pm.
Police described the dead man as an Asian, 170 cm tall and around 30 to 40 years old.
He was wearing a V-neck T-shirt with thin horizontal black and white stripes, and long black trousers over grey tartan-pattern boxer shorts.
On his left forearm the word “ROCKER” or “KOCKER” had been written with a permanent marker.
An examination showed multiple wounds to the back of the dead man’s head. However, an initial examination by pathologists at Vachira Phuket Hospital found that the skull was not broken, and the pathologists believe the damage may have been done after death.
The cause of death has yet to be established. Meanwhile, police are trying to identify who the man is.