The coroner's office on Wednesday identified the man as 32-year-old Jovannta Murphy.
The 55-gallon plastic barrel drum was first seen at the lagoon on Sunday by sanitation workers, but they were unable to retrieve it.
Lifeguard discovers body inside barrel at Malibu Lagoon State Beach
On Monday, a lifeguard was able to bring it to shore and that's when the body was discovered.
How long the barrel was there - and the cause of death of the person inside - are questions that will be subject to investigation.
Authorities said the barrel had a printing company chemical label on it.