An electrostatic precipitator including a charger to charge dust particles in air and a collector to collect the dust particles. The collector includes a collector case including high-voltage electrodes, to which high-voltage is applied, low-voltage electrodes alternately stacked with the high-voltage electrodes so as to be grounded, and first electrode support elements to support the high-voltage and low-voltage electrodes with a distance therebetween. The first electrode support elements include electrode contact terminals to support extreme edge portions of the high-voltage and low-voltage electrodes. The high-voltage and low-voltage electrodes are formed of a conductive material, or a non-conductive material, the surface of which is subjected to conductive treatment. The electrode contact terminals for the high-voltage electrodes are formed of a semiconductive material. Accordingly, it is possible to maintain a constant distance between the electrodes and to prevent insulation breakdown without deterioration in the performance of the collector.