He bought the neighbouring property from Mr Hefner in 2009 for $18m.
Mr Metropoulos is a principal at Metropoulos & Co, which is run by his father Dean.
"The heritage of this property transcends its celebrity and to have the opportunity to serve as its steward would be a true privilege," Daren Metropoulos told The Wall Street Journal.
The mansion was built in 1927 and purchased by Playboy in 1971 for a reported $1.1m, making it the most valuable real estate deal in Los Angeles at the time.
It features a tennis court, free-form swimming pool, wine cellar, home theatre and games house but needs renovating to meet the same standards as other Beverly Hills homes.
Neither party has confirmed what the mansion was sold for.
Mr Hefner, 90, has the right to remain living in the property until his death. The LA estate eventually replaced the original Playboy Mansion, which opened in 1959 in Chicago.