An ion generator includes a high-voltage transformer having a secondary side that is not grounded; a discharge wire-pattern; an induction wire-pattern; a discharge electrode connected to a first terminal via the discharge wire-pattern, the first terminal being disposed on the secondary side of the high-voltage transformer; and an induction electrode connected to a second terminal via the induction wire-pattern, the second terminal being disposed on the secondary side of the high-voltage transformer. The first terminal has a first width. The discharge wire-pattern includes a discharge wide region having a second width greater than the first width. The discharge wide region and the induction wire-pattern at least partly overlap each other in plan view.