An electrostatic atomizer includes an atomizing electrode, a water supply unit for supplying water to the atomizing electrode, a high voltage power circuit and a control unit. The high voltage power circuit applies a high voltage to the atomizing electrode to electrostatically atomizing water supplied to the atomizing electrode and to generate electrically charged water particles. The control unit controls the high voltage power circuit such that the voltage applied to the atomizing electrode is gradually increased at the time of starting the electrostatic atomizer. Further, the control unit may control the high voltage power circuit such that the voltage is increased to a target voltage in steps at the time of starting the electrostatic atomizer, and an increment of the voltage at each step is decreased as the voltage approaches the target voltage.