To provide a sterilization apparatus for efficiently sterilizing medical waste in a classifiable state.SOLUTION: A sterilization apparatus includes: a sterilizing and drying tank 120 in which medical waste is stored; a heat sterilization part 123 that heat sterilizes the medical waste in the sterilizing and drying tank 120 at 125°C or less; a vacuum pump 204 that reduces the pressure inside the sterilizing and drying tank 120 before and after the heat sterilization by the heat sterilization part 123; a charge port 104 leading to the inside of the sterilizing and drying tank 120; and an opening and closing door 106 that opens and closes the charge port 104. The vacuum pump 204 reduces the pressure inside the sterilizing and drying tank 120 when the opening and closing door 106 opens the charge port 104, further reduces the pressure inside the sterilizing and drying tank 120 than when the opening 104 is opened by the opening and closing door 106, on the condition that the opening and closing door 106 closes the charge port 104, and reduces the pressure inside the sterilizing and drying tank 120 on the condition that the heat sterilization by the heat sterilization part 123 is completed.SELECTED DRAWING: Figure 1【課題】 医療廃棄物を分別可能な状態で、効率的に滅菌する滅菌処理装置を提供する。【解決手段】 滅菌処理装置は、医療廃棄物を収容する滅菌乾燥処理槽120と、滅菌乾燥処理槽120内部にある医療廃棄物を125℃以下で加熱殺菌する加熱殺菌部123と、加熱殺菌部123により加熱滅菌する前後に滅菌乾燥処理槽120内部の圧力を減圧する真空ポンプ204と、滅菌乾燥処理槽120の内部へ通じる投入口104と、 投入口104を開閉する開閉扉106とを有する。真空ポンプ204は、開閉扉106が投入口104を開ける場合に、滅菌乾燥処理槽120内部の圧力を減圧し、開閉扉106が投入口104を閉じたことを条件として、開閉扉106により投入口104が開かれた時よりさらに滅菌乾燥処理槽120内部の圧力を減圧し、加熱殺菌部123による加熱滅菌処理が終了したことを条件として、滅菌乾燥処理槽120内部を減圧する。【選択図】図1