To provide a simple and inexpensive half bridge type of inverter device which operates with a high power factor.

This inverter device is equipped with an auxiliary capacitor 42, which is arranged to constitute a closed circuit together with a rectifying power source 10 and both switching elements 21 and 22. This is equipped with the first auxiliary diode 44, which is arranged in the direction of allowing the discharge of one capacitor 61 for arm, in series with that capacitor 61. This is equipped with the second auxiliary diode 46, which is so arranged as to constitute a closed circuit together with the auxiliary capacitor 42, and the first auxiliary diode 44 and to be in normal series with the first auxiliary diode 44. Since the first auxiliary diode 44 is present, charging (a charge current i50) of the auxiliary capacitor 42 is performed. Since the second auxiliary diode 46 is present, discharge current (a discharge current i42) of the auxiliary capacitor 42 flows via the rectifying power source 10.