A plasma device and an air conditioner including a plasma device are provided. The plasma device may include a substrate body, a first electrode disposed on one or a first surface of the substrate body to perform plasma discharge, and a second electrode disposed on the other or a second surface of the substrate body to act with the first electrode. The substrate body may include a third electrode that acts with the first electrode or the second electrode to perform the plasma discharge, and an insulator that surrounds the third electrode.
