Plasma display device and driving method thereof

A plasma display device includes: a plurality of first electrodes, a plurality of second electrodes, a plurality of third electrodes intersecting the first and second electrodes, and a plurality of discharge cells divided into first and second discharge cell groups, the plasma display device representing a gray scale using a unit frame consisting of a combination of a plurality of sub-fields, and its driving method includes: a first address step of selecting discharge cells to be lit from the first discharge cell group; a first sustain step of creating sustain discharges in the discharge cells during the first address step; a second address step of selecting discharge cells to be lit from the second discharge cell group; and a second sustain step of creating sustain discharges in the discharge cells during the second address step; respective rising slopes of the last sustain pulse supplied to one of the first and second electrodes in each of the first and second steps are different from each other.