He has been identified by relatives as Alexey Tsymbalyuk from Blagoveshchensk in Russia's Far East region of Amur.
Police were informed at 11 am that a body had been seen floating in the ocean near the beach, just off the Impiana Resort.
Rescuers on jet-skis brought him back to the beach. Police estimated that he had been dead about three hours. There were no wounds on the body to suggest any cause of death but drowning.
The body of the Mr Tsymbalyuk, who had been staying at the Thara Patong Hotel, was taken to Patong to await arrangements to fly him home.