The 22-year-old from Redhill, in Surrey, was last seen swimming in rough seas, to the east of Palace Pier on Saturday.
A search was started at 07:45 BST and he was found approximately 1km (0.6 miles) from the pier.
Coastguards pulled him from the sea, but he was pronounced dead at the scene.
Sussex Police said the coroner had been informed.
A man who was pulled from the sea after he got into difficulty while swimming in Brighton has died.