To achieve quickly and accurately a characteristic inspection of the whole body formed by integrating oscillators and a circuit part together, on background information that, in a flow measuring device, characteristics of the oscillators and the circuit part comprising a receiving circuit or a transmitting circuit exert an influence on flow measurement accuracy.

This inspection device for a plurality of oscillators 50, 51 and the circuit part 52 constituting the flow measuring device using an ultrasonic wave is constituted so that damping means 55, 56 of the ultrasonic wave are provided in front of the oscillators 50, 51, and that a propagation time of the ultrasonic wave is measured, while the distance 53 between the oscillators 50, 51 is changed by a moving part 70. Hereby, the characteristic inspection of the flow measuring device can be performed quickly and accurately.