An ultrasonic endoscope has an ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged; a backing material layer on a back side of a plurality of ultrasonic transducers, a wiring board including a plurality of electrode pads that are connected to the plurality of ultrasonic transducers; a plurality of shield cables each including a signal wire and a shield member, a wiring portion in which the plurality of signal wires are electrically connected to the plurality of electrode pads; a ground portion that is electrically connected to the shield members and that have heat conductivity; and a first heat conductive member that extends beyond the backing material layer to a side opposite to the ultrasonic transducer array with respect to the backing material layer and that is thermally connected to the ground portion.