The body, discovered about 10 miles off the south-west coast of the island, was reported by the coastguard to police on Wednesday at about 13:45 BST.
Dorset Police said it was working with Hampshire force to investigate if the body is that of Hugh Cox, 61.
He was last seen leaving home for work in Poole in 20 June. His family has been informed of the discovery.
The death of a man whose body was found in the sea off the Isle of Wight is not being treated as suspicious.