The invention relates to a press-filter unidirectional continuous plate pulling device, and aims to provide a press-filter unidirectional continuous plate pulling device with a reliable performance and high work efficiency to fill the technical blank. The device comprises a chain, two chain wheels and a plurality of mechanical arms; and is characterized in that: each mechanical arm comprises a frame, an upper limiting block, a lower limiting block, an executing member, an executing pin shaft, an executing torsion spring, a control member, a control pin shaft, and a control torsion spring; the executing member comprises an executing rod, a hooked hand, and an top pressing head; the upper limiting block, the lower limiting block, the executing pin shaft and the executing torsion spring are all fixed on the frame; the control member comprises a top torsion spring section, a position limiting section, a filter plate top pressing section, and a control section; a rotation hole is arranged on the joint part between the top torsion spring section and the position limiting section; the control pin shaft and the control torsion spring are both arrange on the frame; and the control member is movably connected to the control pin shaft through the rotation hole. The press-filter unidirectional continuous plate pulling device can unidirectionally, continuously and rapidly pull the filter plates in a press-filter and finishes the cake-unloading operation of the press-filter.