A passing motorist saw an unconscious woman lying in a remote area north of Freeway 138 near Gorman Post Road on Sunday, ABC7 in Los Angeles reported.
The woman in her 20s was pronounced dead on the scene after deputies and paramedics arrived. She had suffered from head trauma.
The cause of death is unknown, KABC-TV reported.
Anyone with information about the incident is asked to call the Los Angeles County Sheriff's Department's Homicide Bureau at 323-890-5500 or Crime Stoppers at 800-222-TIPS.