Investigators responded to the 47-year-old's gated home in the 2900 block of Montcalm Avenue around 2:15 p.m. after a woman called 911 to report someone in the house had died.
The man's identity was not immediately released, but Andrew Getty's parents, Ann and Gordon Getty, confirmed it was him in a statement issued through a family spokesman Tuesday night.
"The family has requested that members of the media and the public respect its privacy during this extremely difficult time," the family spokesman said.
The death appeared to be from natural causes, Los Angeles County coroner's Assistant Chief Ed Winter said, but it has been initially called an accident because of medication found at the scene. He said coroner's officials need to await the results of further examination and toxicology tests, which could take up to 10 weeks to process.
"The tentative information that we do have is that he was not feeling good for the last couple months," Winter said, "and he supposedly had an appointment tomorrow with a personal physician."
Officials secured a search warrant before collecting evidence inside the residence and bathroom where Andrew Getty was found dead.
"We went in and made some observations and then we're gonna wait to collect any evidence and the remains," Winter said.
Police spokesman Jack Richter says investigators interviewed the woman and she's being treated as a cooperative witness.
"She's the individual that reported the death investigation to us and is a friend of the decedent," said LAPD Capt. William Hayes.
Andrew Getty is one of four sons of Gordon Getty, a San Francisco multibillionaire who is among the richest men in the United States. Andrew Getty's late grandfather, J. Paul Getty, built Getty Oil Co. into a multibillion dollar fortune.
J. Paul Getty built the Getty Villa in Pacific Palisades to showcase his art collections and also established the J. Paul Getty Trust, which built the Getty Center Museum in Los Angeles.
Forbes Magazine reports the Getty family is worth about $5.1 billion.
The family statement said further statements will be issued as information becomes available.
The Associated Press contributed to this report.