An ultrasound endoscope has a transducer unit that has a top surface, a bottom surface and a side surface connecting the top surface and the bottom surface, and performs transmission and reception of ultrasound on a top surface side, a cable that is for transmitting and receiving an electrical signal to and from the transducer unit and is connected to the side surface, a conductive shield case that has a lead-out port for leading out the cable, and a flexible extension portion extended from at least the top surface side of the lead-out port, and covers the side surface and the bottom surface, and a housing that holds a transducer unit 2 via the shield case, and has a cable insertion path in which the cable and the extension portion are inserted.