A plasma display apparatus comprises a plasma display panel and a driver. The plasma display panel comprises a first electrode, a second electrode, and a third electrode crossing the first electrode and the second electrode. During a first frame, the driver alternately supplies a sustain signal to the first electrode and the second electrode and supplies a constant voltage to the third electrode. During a second frame having a smaller APL of the first frame, the driver alternately supplies a sustain signal to the first electrode and the second electrode and supplies an auxiliary signal to the third electrode so as to correspond to at least one sustain signal of the sustain signals supplied to the first electrode and the second electrode.