Abstract: A high voltage pulse generation device for magnetron is disclosed. The device is divided into a DC voltage generation part, which continuously applies a variable DC voltage at a constant value to the load, and a pulse voltage generation part, which generates a momentary high voltage pulse and supplies the same to the load. The voltage applied to the load is a superposition of the output voltages from the two devices. Further, a pulse transformer demagnetization power supply is provided. A high voltage pulse waveform is obtained by momentary resonance and the pulse transformer using a low voltage at the time of pulse generation, thereby reducing the insulation space required and the size and the weight of the device. It is also possible to adjust the peak value and pulse cycle of the DC voltage applied to the load in addition to the pulse voltage.