The ultrasonic operating apparatus includes an ultrasonic transducer that generates ultrasonic vibrations, and a probe that has a distal end portion and a proximal end portion, the proximal end portion being coupled to the ultrasonic transducer, and to which ultrasonic vibrations output from the ultrasonic transducer are transmitted, where the probe has a probe main body having a length of an integral multiple of about a half wavelength of the ultrasonic vibrations and an adjusting portion that changes a weight and a dimension of the probe main body to adjust a resonance frequency of the probe main body.
