In a plate processing machine such as punch press provided with a workpiece moving/positioning device (49) including a carriage base (53) movable in the longitudinal Y-axis) direction of the machine and a carriage (69) movable in the lateral (X-axis) direction of the machine, a carriage drive unit of an X-axis motor (79) and a reduction gear (77) for moving the carriage is disposed near a middle portion of the carriage base to balance the workpiece moving/positioning device, so that workpiece processing precision can be improved. Further, the width of a caterpillar table (82) fixed to the carriage base between two movable tables (81) also fixed to the carriage base is reduced to prevent vibration of the caterpillar table, so that scratches under the surface of a workpiece can be reduced. Furthermore, a caterpillar carry table (93) is disposed behind a process position where a tool set is arranged remote from the caterpillar table in synchronism with the caterpillar table in motion so as to be inclined front down to carry out processed parts in the same rearward direction.