<p>Disclosed is a thin and small-sized piezoelectric resonator with a built-in capacitor having excellent reliability. In this piezoelectric resonator, a pair of vibrating electrodes are formed on both major surfaces of a piezoelectric substrate, and a sealing substrate which is made of a ceramic material for forming an electric capacitor is joined onto one of the vibrating electrodes via a frame member while another sealing substrate made of a resin material is joined onto the other vibrating electrode via another frame member.</p>
