Abstract: A pressure cooker with a humidity sensor or gas sensor, wherein a micro-computer reliably detects the point at which the internal pressure of a pressure cavity reaches a prescribed value by using this sensor by detecting the point at which a pressure control valve begins to operate and begins to discharge a large quantity of excess vapor or gas etc. from the pressure cavity to the outside, with a result which is equivalent to that of a direct measurement of the internal pressure with a pressure sensor, thereby attaining an accurate measurement without bringing the humidity or gas sensor into contact with the pressure cavity.