A touch detection device capable of operation by a light touch, and of preventing false operations even when used in water handling equipment includes a sensing portion for sensing contact by a target object; a vibration excitation element attached to this sensing portion, a drive circuit for exciting vibration in the sensing portion, and a contact determining circuit for determining whether a target object is contacting a sensing portion based on vibration of the sensing portion after stopping the application of an AC voltage to the vibration excitation element by this drive circuit.