The Carnival Victory cruise ship arrived back in Miami on Friday after a 26-year-old male passenger went overboard earlier in the day, the cruise line said.
The US Coast Guard released the ship from search-and-rescue efforts but is continuing to search.
The man went overboard about 35 miles south of the Florida Keys, officials said.
Coast Guard spokesman John Lally said the Coast Guard is using a fixed-wing aircraft, an HC-144 Ocean Sentry and a Coast Guard cutter in the search. A Coast Guard helicopter used earlier in the day returned to base, he said.
Lally said he didn’t know how long the search would continue, noting that swells, temperatures and currents will be considered.