A stable address discharge in a plasma display device is generated without increased voltage to cope with increase in the cumulative current-carrying time of a panel with high luminance. A cumulative time calculating circuit for calculating cumulative current-carrying time of the panel and a driving circuit for driving the panel. The driving circuit delivers collected power to the display electrode pairs and clamps each voltage of the display electrode pairs to power-supply voltage and base potential. A sustain period has a period, during which the voltage of the display electrode pairs is clamped to base potential, between the sustain pulse for generating the last sustain discharge in the sustain period and the immediately preceding sustain pulse. The length of the period is changed according to the cumulative current-carrying time calculated by the cumulative time calculating circuit.