A plurality of connection conductors (61) are shielded from each other as a result of: the plurality of connection conductors (61) being formed on a printed wiring board (6) and connecting between each of a plurality of lead signal lines (24) drawn out from a plurality of piezoelectric elements (2) and each of a plurality of communications cables connected to an ultrasonic diagnostic device main body and a ground conductive layer (64) for connection conductors being formed, via an insulating layer (63) for connection conductors, on the printed wiring board (6) so as to cover the outer perimeter of each of the plurality of connection conductors (61).
