A surgical operating apparatus includes an ultrasonic transducer which generates ultrasonic vibration, a transducer cover including a storing section which stores the ultrasonic transducer, an electric contact portion provided on an outer peripheral surface of a distal end portion of the transducer cover, and an insulative projection portion which is provided at a distal end portion of the transducer cover and projects more radially outward than an outer peripheral surface of the electric contact portion.