In order to remove a pathogenic effect of a microorganism in a room or a work space in a short period of time, an ion diffusing apparatus, which includes an ion generator (17, 18) for generating positive ions each including H+(H2O)m and negative ions each including O2−(H2O)n, where m and n are arbitrary integers, and a blower for delivering the positive ions and the negative ions, which are generated from the ion generator (17), from a blowout opening, is operated to widely distribute, with a high concentration, the positive ions and the negative ions in the room.