Provided is a support device for a resonator capable of supporting the resonator at any position and efficiently applying ultrasonic vibration to an object by vibrating the resonator stably with a predetermined frequency. In order to support the resonator (7), a first clamp means (21) and a second clamp means (22) are inserted into the first supported part and the second supported part of the resonator (7), respectively. At least the portions of the first clamp means and the second clamp means, which are brought into contact with the first supported part and the second supported part, respectively, are formed by support members. The support members are made of a material having a logarithmic decrement of 0.01 to 1, or a material having a sound velocity higher than 5900 m/s.