PURPOSE: To perform the sorting of a light wt. substance easily at a high speed, by a method wherein an electrode plate is inclined and the interval between the upper surface of a sorting table and the electrode plate is made small at the outlet side to equalize a whole substance to be sorted even if the accumulated thickness thereof at the inlet side is thick.

CONSTITUTION: An electrode plate 5 is arranged in an inclined state in such a manner that the interval between the sorting table 1 and a flat plate 1a is made large at the inlet side 1X and made small at the outlet side 1Y. By this structure, even if the accumulated thickness of a substance to be sorted becomes thick at the inlet side, the interval between the electrode plate and the upper surface of the substance to be sorted becomes equal over the whole of the sorting table and sufficient Coulomb force is acted on the substance to be sorted even at the outlet side to perform the sorting of light weight substances to be sorted easily at a high speed.