An ultrasonic endoscope includes an ultrasonic vibrator unit provided at a distal end part, the ultrasonic vibrator unit being composed of at least an ultrasonic vibrator array and a first thermally conductive member, the ultrasonic vibrator array having the plurality of ultrasonic vibrators that are arranged in a cylindrical form, the first thermally conductive member being disposed thermally in contact with the ultrasonic vibrator array; a plurality of cables that are electrically connected to the ultrasonic vibrator array; and an electrically conductive structural body that is disposed to extend from a distal end side toward a proximal end side of the ultrasonic endoscope. The ultrasonic vibrator unit and the electrically conductive structural body are connected to each other via an electrically insulating second thermally conductive member. Thus, the ultrasonic endoscope that has a heat release structure which transmits the heat generated from the ultrasonic vibrator to the electrically conductive endoscopic structure housed in a distal end part and which can efficiently release the heat therefrom while electric safety is secured; and that can prevent a burn of an alimentary canal by suppressing a temperature rise of surfaces of the ultrasonic vibrators is provided.