A thin-film ESD protection device that includes a semiconductor substrate having a first and second principal surfaces); a first insulating layer disposed on the first principal surface; a second insulating layer disposed formed on the second principal surface; and first and second input/output electrodes, ground electrodes, a diode element, a capacitor element, and an inductor element. The capacitor element and the diode element are formed adjacent to the first principal surface, whereas the inductor element is formed adjacent to the second principal surface. The inductor element is connected to the first input/output electrode and the second input/output electrode by a first via conductor and a second via conductor, respectively, that pass through the semiconductor substrate from the first principal surface to the second principal surface.