To provide a high voltage generation circuit capable of efficiently applying high voltage to a discharging electrode without loss of voltage by a simple circuit configuration and to provide an ionizer.

In this high voltage generation circuit 6 comprising positive polarity and negative polarity voltage doubler rectifier circuits 6a, 6b, and used for the ionizer generating positive and negative ions by corona discharge of the discharging electrode by applying positive or negative direct-current high voltage alternately between the discharging electrode 3 and a ground electrode, current-limiting resistances are provided between output terminals of the positive polarity rectifier circuit and between output terminals of the negative polarity rectifier circuit respectively, and the high voltage generation circuit 6 when it is connected with the positive polarity rectifier circuit and the negative polarity rectifier circuit in series and high voltage is applied to the discharging electrode becomes a circuit equivalent to a circuit wherein the discharging electrode and current-limiting resistances of one voltage doubler rectifier circuit generating the high voltage and the other voltage doubler rectifier circuit not generating the high voltage are connected in series.