PURPOSE: To make the vibration frequency stable by loading a pressure or tensile mechanic force to the outer circumference of a crystal resonator so as to cancel or decrease a vibration frequency change due to the temperature of the crystal resonator.

CONSTITUTION: An electrode 13 on the both faces of a crystal plate 7 is in electric contact with the couple of support plates 8 provided to the outer circumferential face of a crystal plate 7 symmetrical horizontally, and an object (= deforming body) 12 deformed by a temperature is bonded to the upper part of the support plates 8 so that both the support plates 8 are electrically insulated. A bimetal deformed by a prescribed quantity at a prescribed temperature is employed for the deforming body 12. Thus, when the temperature rises, the distance between the support plates 8 is widened and the crystal plate 7 receives a tensile force. Moreover, when the temperature is lower, the distance between the support plates 8 is made narrow, resulting in pressing the crystal plate 7.