PURPOSE: To simultaneously supply a pulse voltage and D.C. base voltage to the electric dust collector by means of a power supply device.

CONSTITUTION: In the pulse power source device for electric dust collector impressing the pulse voltage to be outputted from a pulse generator to an electric dust collector 10 after rising the pressure in a pulse transformer 9, a coupling capacitor 11 intervenes between the pulse transformer 9 and the electric dust collector 10. Serially connected diodes 12 and reactor 13 are parallely connected to the coupling capacitor 11 or the diode is parallely connected to the electric dust collector 10. Thus, the D.C. voltage is supplied from the coupling capacitor 11 to the electric dust collector 10 with the inversion of the polarity of the electric charge remained in the coupling capacitor 11 after impressing the pulse voltage.