Officers were dispatched to the intersection of La Habra and Harbor Boulevard around 5:30 a.m. where they found a man lying dead in the street.
The driver of the vehicle involved was unharmed.
Police have not determined the identity of the victim and are unsure of what caused the accident, but an investigation is underway.
Investigators are asking any witnesses who may have seen the accident to come forward by contacting the department at (562)905-9750.