The retired watersports enthusiast was reported missing just before 10am today after he surfed from Hayling Bay.
An RNLI lifeboat team from Portsmouth were scrambled to find the man, conducting a wide search of the waters around Hayling Island.
The stranded surfer was spotted 400m from the entrance of Portsmouth Harbour by an eagle-eyed crewman on a dredging ship as the vessel entered the city.
Aaron Gent, of Portsmouth RNLI, said the man was lucky not to have been injured.
‘He was pretty cold and shaky when the lifeboat crew found him,’ he said.
‘But honestly, the gentleman was very lucky to have been spotted at all.
‘It’s not very often we get large ships coming out the channel – that particular ship only goes out once or twice a day. So the man was very lucky.’
The man was taken back to Hayling and treated by the Coastguard rescue team.