PURPOSE: To economically and sufficiently remove and recover a stuck and residual treating liquid by equipping a treating liquid-recovering unit which is connected to the suction system of an aspirator, sucks and removes the stuck treating liquid by bringing a suction port into contact with the principal surface of a conveyed and treated printed wiring board to arrange the suction port thereon.

CONSTITUTION: Aspirators are installed on the way of a second treating liquid-supplying system 16 and perform sucking action by forming a decompressed region in accordance with the flow velocity or the flow rate of a treating liquid 13 flowing in a pressurized state through the second treating liquid-supplying system 16. A treating liquid- recovering unit 20 is so constituted, that one end face is equipped with a long-sized suction port 20a opened in a wide and large diameter and that other end is connected to the suction systems 19a of the aspirators 19. The suction port 20a is brought into contact with the width direction of the principal surface of a treated printed-wiring board 12 and the stuck and residual treating liquid 13 is forcedly sucked and removed. Further, in this case, pressure type rollers 20b are attached on both sides of the long- sized suction port 20a and the surface of the treated printed-wiring board 12 is regulated and the stuck treating liquid is easily sucked, removed and recovered.