To provide an electrostatic separation apparatus and an electrostatic separation method which enable a stable separation of ash (separating it into ash of a high unburned combustible-component content and ash of a low unburned combustible-component content) without generating a spark even if coal ash coming out of a boiler of a coal-fired power station has a high unburned combustible-component content of 15 to 30%, reusing the ash of a high unburned combustible-component content as a fuel, and making the ash of a low unburned combustible-component content reusable as an auxiliary raw material of, for example, a concrete.

The electrostatic separation method for separating ash containing unburned carbon contained in coal ash by virtue of static electricity enables a separation of ash containing unburned carbon contained in coal ash by introducing the coal ash into an electrostatic separation zone comprised of a direct current electric field generated between a lower electrode and an upper electrode using either of the two electrodes as an anode and the other as a cathode, which lower electrode is roughly planar and which upper electrode is comprised of a high dielectric resin member and is disposed above the lower electrode. An apparatus for carrying out the method is also disclosed.