An ultrasonic receiver receives ultrasonic waves reflected at a plurality of portions of the body of a person to be measured, and thus the person to be measured needs to input the approximate height of himself/herself. An electrostatic capacitance sensor includes a transmission electrode and a reception electrode. The electrostatic capacitance sensor measures a mutual capacitance between the transmission electrode and the reception electrode by a mutual capacitance method. A variable frequency pulse generator generates a pulse supplied to the transmission electrode. A control apparatus allows the variable frequency pulse generator to sweep the frequency of the pulse and allows the electrostatic capacitance sensor to measure the mutual capacitance to identify a frequency at which the measured mutual capacitance is minimized. The control apparatus obtains the height of a person to be measured on the basis of the identified frequency.
