PURPOSE: To surely attain separation even relating to a plate of nonmagnetic material by providing a contact part having a pair of friction surfaces brought into contact with both end surfaces of the plate material in a plate material loading part.

CONSTITUTION: A plate material separating device 10 provided upward of a material carriage 1 is constituted of the first/second contact parts 11, 12 arranged to be opposed by interposing a plate material W1 and a drive mechanism 30 of driving each contact part. A knurling bar of performing knurling work of the surface is mounted R point ends of the contact parts 11, 12, to provide, for instance, stainless steel-made wire brushes 19, 43 implanted sideward of this knurling bar. In a condition that the plate material W1 is brought into press contact by the first/second contact parts, the uppermost plate material is sucked to be held by a sucker pad, and it is lifted. Here by applying friction force to act with the contact parts 11, 12 into press contact with both end surfaces of the loaded plate material on the material carriage 1, large separating force acts between the uppermost positioned plate material and the plate material downward thereof, to separate the plate material.