A power supply circuit for plasma generation by which a large quantity of generated plasma can be smoothly obtained without increasing the sizes of an apparatus. An electric discharge generating electrode is composed of two or more first electrodes and one or more second electrodes. An LC series circuit is provided by connecting a capacitor C and a coil L in series between one of outputs of an alternating high voltage generating circuit which generates an alternating high voltage to be applied between the electrodes of electric discharge generating electrode, and the first electrode. When electricity is discharged in one of the electrode pair, voltage drop is suppressed by the coil, and since electric discharge from the other electrode pair is induced without being disturbed, a large quantity of plasma can be smoothly generated by common use of the alternating high voltage generating circuit.