A plasma display panel, the light emission efficiency of which has been improved without increasing the discharge start voltage, is disclosed. In a three-electrode type PDP, a fourth (Z) electrode is provided at the portion between a first (X) electrode and a second (Y) electrode between which a main discharge (a sustain discharge) is caused to occur for a display and at least one of the distance between the first electrode and the fourth electrode and the distance between the second electrode and the fourth electrode changes gradually in a cell.