A composite electronic component including a resonator element and a capacitor element fixed together by adhesive material. The capacitor element is longer than the resonator element, so that side steps are defined on both end portions of the elements. First and second lead terminals are connected by solder with first and second capacitor electrodes located on a front surface of the capacitor element and with resonator electrodes located on side surfaces of the resonator element exposed at the side steps. A third lead terminal is connected by solder with a third capacitor electrode located on a rear surface of the capacitor element. Therefore, the thin and miniature composite electronic component adapted for a Colpitts oscillation circuit is obtained at a low cost.