To improve capacity and efficiency of separation and acquire stable operation by reducing sparks in an electrostatic separation system of conductive particles from mixed particulates of the conductive particles and insulating particles.

Conveying air 7 is introduced along an upper mesh electrode 3 from one side and discharged from the other side with conductive particles entrained by the air 7. This allows the conductive particles to float selectively in the vicinity of the upper mesh electrode 3 with low field intensity and the insulating particles to move to a lower outlet while being held by a lower perforated electrode 4 and thus can separate the particles from each other efficiently and easily. The sparks can be reduced by lowering the field intensity.