A surgical operating apparatus includes an ultrasonic transducer (6) which generates ultrasonic vibration, a transducer cover (7) including a storing section (211) which stores the ultrasonic transducer (6), electric contact portions (131, 132, 133) provided on an outer peripheral surface of a distal end portion of the transducer cover (7), and insulative projection portions (123a,124a,125a) which is provided at a distal end portion of the transducer cover (7) and projects more radially outward than an outer peripheral surface of the electric contact portions (131, 132, 133).