The present invention addresses the technical problem of providing a work apparatus orientation control device which is capable of preventing hunting and controlling the tilling depth in the slow lift speed region of a hydraulic lift cylinder (71). A ground working apparatus (24) is mounted via a link mechanism (23) so as to be capable of elevating/lowering to a work vehicle (1) supported so as to be drivable by a front vehicle wheel (3) and a rear vehicle wheel (4). The work vehicle (1) is further equipped with the hydraulic lift cylinder (71) and a lift valve (81) which elevate and lower the ground working apparatus (24) and a sensor wire (111) which detects the angle of a ground working sensor (43) in the ground working apparatus (24). A sensor input restricting body (112) is further provided at a location along the connection between the lift valve (81) and the sensor wire (111).
