PROBLEM TO BE SOLVED: To provide a high-pressure steam sterilizer that can prevent water from adhering to a valve part of a solenoid valve for opening and closing an air supply flow path which supplies air into a chamber and also achieve expected sterilization of an object to be sterilized.SOLUTION: A filling port of a filling flow path 13 for filling water into the chamber 4 is opened to a lower part in the chamber, the air supply flow path 11 for supplying outside air into the chamber penetrates the upper part of the chamber through the solenoid valve 14 disposed upper side than the filling flow path outside the chamber, and an air outlet 11B of the air supply flow path is opened to a heater chamber 5A.COPYRIGHT: (C)2013,JPO&INPIT【課題】チャンバー内へ空気を供給する空気供給流路を開閉する電磁弁の弁部分に水が付着することがないようにすると共に、被滅菌物の所期の滅菌が達成できる高圧蒸気滅菌器を提供する。【解決手段】チャンバー4内に注水する注水流路13の注水口がチャンバー内の下部に開口し、チャンバー内に外気を供給する空気供給流路11は、チャンバーの外側で注水流路よりも上方に配置した電磁弁14を介してチャンバーの上部を貫通し、ヒータ室5Aに空気供給流路の空気出口11Bが開口した。【選択図】図1