The present invention relates to a crystal oscillator that is provided with a crystal element; a main surface electrode configured of a first underlayer formed on each of two main surfaces of the crystal element and a first surface layer of Au superimposed over the first underlayer; an end surface electrode having a second underlayer formed on the crystal element to extend over the main surface electrode and a second surface layer of Au superimposed to cover the second underlayer; a supporter for holding the crystal element in the horizontal direction, bonded to the end surface electrode by a eutectic alloy comprising at least Au; and a base on which the supporter stands. An intermediate layer is provided between the second underlayer and the second surface layer of the end surface electrode; the intermediate layer protrudes further towards the center over the main surface electrode than the second surface layer; and also the intermediate layer is formed of a metal having the characteristic of increasing the adhesive strength between the underlayer and the second surface layer as well as that of the eutectic alloy. The present invention provides a crystal oscillator in which bonding is done with a eutectic alloy that has a higher bond strength, thus preventing peeling of the electrodes.