An AC high voltage power supply device includes a comparison circuit configured to compare a first signal of a sinusoidal waveform and a second signal of a triangular waveform; a switching amplifier circuit configured to perform a switching operation based on a comparison result signal output from the comparison circuit to perform signal amplification; a conversion circuit configured to convert a waveform of a switch signal output from the switching amplifier circuit into a sinusoidal waveform; a transformer configured to boost a voltage of a converted signal output from the conversion circuit; and a control circuit configured to perform feedback control on the first signal input to the comparison circuit based on a monitoring signal including an input signal or an output signal of the transformer, so that a peak level of the output signal of the transformer becomes a desired peak level.