Yarmouth RNLI Lifeboat and Isle of Wight coastguard teams were among emergency crews called to The Needles on Sunday afternoon, after a man’s body was discovered.
A passing vessel alerted HM Coastguard to a fishing boat, with one person on board, just before 2pm.
Hampshire Constabulary said: “We were called at 2.30pm, after the body of a 68-year-old man from Freshwater was found in a boat at sea.
“The death is not being treated as suspicious and a file is being prepared for the coroner.”
The coastguard helicopter from Lee on Solent was also on the scene.
The man’s next of kin have been informed.