Frank Daniel Austin, 34, of Rowland Heights, was last seen going into the water at Salt Creek Beach around 4 p.m. on Sunday, Sept. 2. His mother reported him missing just after 7 p.m., authorities said.
Austin's disappearance prompted a four-day search by the U.S. Coast Guard and the Orange County Sheriff's Department's Harbor Patrol.
He was swimming in an area where lifeguards were posted, but there was a high surf advisory in effect, with remnants from Hurricane Ileana generating waves up to 7 feet tall.
The search for Austin was scaled back on Monday, with deputies changing the operation to a recovery effort.
Divers resumed the search for Austin on Wednesday morning, but stopped about three hours later.
An autopsy will be conducted this week to determine the cause of death, coroner's officials said.