Investigators believe the woman met with foul play, but are not elaborating.
"When officers arrived they found from hotel staff a deceased female, 24-year-old black female in the room. And information at the scene and evidence leads us to believe that this is a homicide," said Lt. Travis Whitman from the Garden Grove Police Department.
On Saturday police identified the woman as 24-year-old Ashley Nicole Lilly. It is unclear if Lilly was a guest at the hotel or if she was meeting someone there.
Lt. Whitman said the hotel management is cooperating, including providing security camera video.
Crime scene investigators are still trying to gather evidence and put together what led to the death of the young woman. Police say they are working on some leads.
Anyone with information about the case is asked to call Garden Grove police at (714) 741-5704.