PROBLEM TO BE SOLVED: To provide a gas generator capable of detecting whether a hole is made in a vibration plate or not.SOLUTION: The gas generator includes: a first reservoir part having the vibration plate attached to close a first opening provided on the bottom surface, and having a first space for storing a liquid to be sealed when pressurized or depressurized a vaporization part for vaporizing the liquid atomized in the first reservoir part a second reservoir part having a second space for storing propagation water to propagate ultrasonic vibration, a second opening and an ultrasonic vibrator on the bottom surface, and sealing the second space together with the first reservoir part when the second opening is closed a pressure regulation device for pressurizing or depressurizing the first space and a pressure measuring device for measuring the pressure in the second space via the second opening.
