Brentwood is an affluent district in the western Los Angeles, California, United States; it is not to be confused with Brentwood, California, in the San Francisco Bay Area of Northern California.

Located at the base of the Santa Monica Mountains, bounded by the San Diego Freeway on the east, Wilshire Boulevard on the south, the Santa Monica city limits on the southwest, the border of Topanga State Park on the west and Mulholland Drive along the ridgeline of the mountains on the north.