Raymond Connor was found dead early on Thursday morning after his worried sister and crew members on the yacht Hampshire 2 called police to report him missing.
The 78-metre yacht is owned by Sir Jim Ratcliffe, founder and chief executive of chemical giants Ineos.
Connor had left the yacht after it docked in Imperia, near the northern city of Genoa, on Monday morning and sent a video and selfie to his sister showing him on the roof of an abandoned building at the port’s maritime museum.
He was a parkour enthusiast which involves running, climbing and jumping over obstacles and is inspired by military training.
He later failed to call his sister or report back for duty and the alarm was raised.
It is believed Connor misjudged a jump and fell around 30 feet through a plastic roof.
A post mortem is due to be carried out on Friday.