PURPOSE: To prevent an electric shock accident by setting a current detector for monitoring discharge current caused across display electrodes and, if a panel is broken, stopping supply of high voltage to a display electrode by means of variation in output of the discharge current.

CONSTITUTION: A power voltage control circuit 9 is connected to a driver group 10 and a high voltage source 11, and controls power to be supplied to the driver group 10 in accordance with output signals from a current detector 8. If a plasma display panel 1 is broken and an electrode group 4 and an auxiliary electrode 5 are exposed, a space filled with neon gas 7 becomes atmosphere, which eliminates discharge current between the electrode group 4 and the auxiliary electrode 5. Its variation is detected by the current detector 8, and the power voltage control circuit 9 stops supplying voltage for driving the plasma display panel 1 to the driver group 10. Thus application of high voltage to the electrode group 4 and the auxiliary electrode 5 is interrupted.