There is provided a piezoelectric actuator and the like capable of efficiently transmitting vibration between an object (e.g., a housing of an electronic device) and a piezoelectric ceramic vibrator. The piezoelectric actuator 50A includes a piezoelectric ceramic vibrator 15 and a holder 12 to hold an edge section thereof and functions as, for example, a vibrator by propagating deflective vibration of the vibrator 15 via the holder 12 to an elastic body 14 as the object. A subsidiary holder 13 is disposed between the vibrator 15 and the elastic body 14, and part of the deflective vibration of the vibrator 15 is propagated via the elastic body 14.