Mosley, 67, had been missing since Wednesday after he went for a walk alone along a coastal path in searing heat.
Police spokeswoman Constantina Dimoglidou had earlier said that the body of a person believed to be Mosley had been found in the area of Agia Marina, but that identification was pending.
"The mayor of the island and a state TV ERT journalist were filming the area of Agia Marina, when they spotted the body," said deputy mayor Nikitas Grillis. "It is certainly him."
An image taken from a computer screen of a CCTV and released to Reuters on Jun 7, 2024, shows what is believed to be British TV doctor Michael Mosley on a street on the Greek island of Symi, Greece.
Another police official said the body had been found on rocky terrain, close to the sea, dismissing earlier reports that said he was found in a cave. Police were investigating the scene.
Mosley, who was on the island with his wife, was last seen alive at 1.30pm local time on Wednesday.
He had disappeared after setting out along a rocky coastal path from Agios Nikolaos beach to the village of Pedi, triggering a search operation.