A sterilization device (1) includes a reactor (4) in which calcium oxide and water are reacted a sterilization space (6) that is filled with water vapor generated in the reactor (4) a sterilization part (5) formed in the sterilization space (6) on which a sterilization object (2) to be sterilized is placed a device main body (3) that encases the reactor (4), the sterilization space (6) and the sterilization part (5) to bring the sterilization space (6) into an airtight state a supply unit (9) for supplying combustion gas into the sterilization space (6) and a discharge passage (13) through which a gas mixture in the sterilization space (6) is discharged to the outside.
