PROBLEM: To reduce noise generated by water and gas discharged after a sterilization treatment, and prevent adhesion of condensation water on an object to be sterilized.SOLUTION: A sterilizer includes a can body 2 having a heater 12, and capable of housing an object to be sterilized 3 a steam discharge pipe 32 connected to the can body 2, and having an opening and closing means 34 for opening and closing a channel to enable discharging of steam and a discharged steam tank 35 provided partway along the steam discharge pipe 32, and having a greater channel cross-sectional area than that of the steam discharge pipe 32.
