The baby's body was found on a conveyor belt at GreenWaste Recovery shortly after 3:30 a.m., authorities said.
The Coroner's Office will conduct an autopsy to determine the manner and cause of death.
Anyone with information is asked to contact Detective Ramon Sanchez or Detective Sergeant Isidro Bagon of the San Jose Police Department's Homicide Unit at 408-277-5283. Persons wishing to remain anonymous may call Crime Stoppers at 408-947-7867.
Stay with ABC7 News for the latest details on this developing story.