Bynes, 27, previously spent weeks at the psychiatric facility in Ventura County, but her mother Lynn and temporary conservator requested her transfer to UCLA because she felt the actress would get better care there, the celebrity news website said.
Bynes was transferred Thursday when a bed became available at UCLA, the report said.
The former child star was placed on an involuntary psychiatric hold in late July after she allegedly caused a disturbance when she tried to break into a retirement community in her hometown of Thousand Oaks, Calif.
The following night, she reportedly set a small fire in a driveway, which led to police involvement and her eventual hospitalization.
The actress is known for her work on TV's "What I Like About You" and "The Amanda Show," as well as in the films "Hairspray" and "What a Girl Wants." Her most recent major screen credit was a supporting role in 2010's "Easy A."
Her once-bright career has been eclipsed in recent years by her bizarre Twitter rants and frequent brushes with the law.