A piezoelectric transformer that includes a base and an upper layer supported by the base. The upper layer includes a first piezoelectric layer that includes the portion of the upper layer that is interposed between an output electrode and an intermediate electrode, and a second piezoelectric layer that is superposed with the first piezoelectric layer and includes the portion of the upper layer interposed between the intermediate electrode and an input electrode in at least n vibration portions. Moreover, the input electrode includes multiple input electrode pieces and the output electrode includes multiple output electrode pieces. In addition, wiring lines are routed such that voltages of opposite phases can be respectively applied to a first input electrode piece group and a second input electrode piece group with the potential of the intermediate electrode serving as a reference.