A supporting force inspection device for inspecting a supporting force of a vibration suppression member interposed between bend portions of a plurality of heat transfer tubes of a steam generator includes: an acceleration sensor for detecting a vibration state of the bend portion; a sensor holding part disposed inside the heat transfer tube and configured to hold the acceleration sensor; and a vibration force generation part configured to generate a vibration force for vibrating the heat transfer tube along a plane in which a curvature circle of the bend portion exists. The vibration force generation part is configured to cooperate with the sensor holding part and vibrate the heat transfer tube along the plane in which the curvature circle exists.