The victims' vehicle hit a third vehicle before hitting a tree, while driver of the white SUV fled the scene.
The 39-year-old woman and her husband were rushed to a nearby hospital, where the woman later died from her injuries. The husband is still being treated for multiple injuries.
The people in the third vehicle were not hurt.
Anyone with information about the accident is urged to call the L.A. County Sheriff's Compton Station at (310) 605-6500.