A mask device with blower comprising: an exhaust valve that is provided on an anterior portion of a face body , and moves in an opening direction at the time of exhausting air and in a closing direction at the time of inhaling air; an inhalation valve that is provided on the anterior portion of the face body , and moves in a closing direction at the time of exhausting air and in an opening direction at the time of inhaling air; a blower that is driven by a motor , and supplies external air to an inner portion of the face body through the inhalation valve when the blower operates; and a sensor for blower control that is disposed in the vicinity of the exhaust valve , and detects a movement position of the exhaust valve at the time of inhaling air in a non-contact state with respect to the exhaust valve and generates a signal; wherein, when a person who wears the mask device inhales air, power is supplied to the motor to operate the blower , and when the person exhausts air, power supply to the motor is stopped or reduced, based on the signal that is output from the sensor for blower control , the mask device with blower further comprising: a sensor for warning that detects a position of the exhaust valve which is caused to move when an internal pressure of the face body is lower than an outer atmospheric pressure in a non-contact state with respect to the exhaust valve and outputs a signal, at the time of inhaling air; and a control circuit that receives the signal output from the sensor for warning and operates a warning device , wherein each of the sensor for blower control and the sensor for warning is composed of a non-contact sensor that monitors a state of the exhaust valve . an exhaust valve that is provided on an anterior portion of a face body , and moves in an opening direction at the time of exhausting air and in a closing direction at the time of inhaling air; an inhalation valve that is provided on the anterior portion of the face body , and moves in a closing direction at the time of exhausting air and in an opening direction at the time of inhaling air; a blower that is driven by a motor , and supplies external air to an inner portion of the face body through the inhalation valve when the blower operates; and a sensor for blower control that is disposed in the vicinity of the exhaust valve , and detects a movement position of the exhaust valve at the time of inhaling air in a non-contact state with respect to the exhaust valve and generates a signal; wherein, when a person who wears the mask device inhales air, power is supplied to the motor to operate the blower , and when the person exhausts air, power supply to the motor is stopped or reduced, based on the signal that is output from the sensor for blower control , the mask device with blower further comprising: a sensor for warning that detects a position of the exhaust valve which is caused to move when an internal pressure of the face body is lower than an outer atmospheric pressure in a non-contact state with respect to the exhaust valve and outputs a signal, at the time of inhaling air; and a control circuit that receives the signal output from the sensor for warning and operates a warning device , wherein each of the sensor for blower control and the sensor for warning is composed of a non-contact sensor that monitors a state of the exhaust valve . <EOS>