<p>[Problem] To prevent a reduction in the amount of the ions released while controlling the generation of electromagnetic noise. [Solution] A high-voltage generating circuit unit (2) that supplies high voltage to an ion generating element (1) that generates ions is accommodated in a housing (3), and the high-voltage generating circuit unit (2) is sealed by a filling resin (22). A release opening (12) for releasing generated ions is formed in the housing (3), and other than the release opening (12), the outer surface of the housing (3) is covered by a shielding case (30). A passage opening (33) leading to the release opening (12) is formed in the shielding case (30). The periphery of the passage opening (33) of the shielding case (30) is covered by an electrically insulating covering sheet (36) such that released ions do not become attached to the shielding case (30). The ions released from the release opening (12) are not adsorbed by the shielding case (30) that is covered with the covering sheet (36).</p>
