PURPOSE: To enhance separation accuracy in an electrostatic separation of different kind resin materials having mutually different static charge characteristic.

CONSTITUTION: A static charge quantity of a resin material charged in a polarity different from its original static charge characteristic is reduced by imparting positive or negative charge by corona discharge for the resin materials 5, 6 charged so as to have mutually different polarities by the friction, and also abnormal electrification is dissolved by electrifying the resin material on the polarity of its original static charge characteristic and a positively charged resin material is separated from a negatively charged resin material by supplying the resin material into an electric field.