The decision comes after a months-long battle between the council and the owners of the home in the upscale Brentwood neighbourhood. Next-door couple Roy Bank and Brinah Milstein bought the property in July 2023 for $US8.35 million ($A12.56 million) with plans to demolish the house to expand their estate, according to the Los Angeles Times.
The couple obtained a demolition permit soon after, but council member Traci Park last year introduced a motion to protect the home by granting it landmark status, receiving approval from the Cultural Heritage Commission and the Planning and Land Use Management Committee, the Los Angeles Times said.
"There's no other person or place in the city of Los Angeles as iconic as Marilyn Monroe and her Brentwood home," Park said before Wednesday's council vote.
"To lose this piece of history, the only home that Monroe ever owned, would be a devastating blow for historic preservation."
Monroe bought the Spanish Colonial-style home in 1962 for $US75,000. It was the only residence she ever owned before she died there six months later of an apparent drug overdose.
Bank and Milstein sued the city in May for acting unconstitutionally in order to preserve the house, according to the Los Angeles Times.
A judge denied their injunction request to stop the historical designation, and a trial-setting conference for the pending lawsuit is set for August 13, according to The New York Times.
