The purpose of the present invention is to produce a favorable effect on the mental state of a user in an air-conditioned space by emission of ions. An ion generator (100) brings about an ion concentration in which the number of ions per 1 cm3 is 50,000 or more in an air-conditioned space.一種離子產生裝置,其藉由釋出離子,對被空調空間內之使用者的精神狀態賦予良好影響。離子產生裝置(100)將被空調空間設為每1cm3之離子個數為5萬個以上之離子濃度。