A flash phenomenon of OLEDs at the time of power source ON of a display device is suppressed. The OLED emits light when reference potentials VSS and VDD are applied from power source lines to the OLED's cathode and anode respectively. While the anode can be connected to one of the power source line via a driving TFT and a lighting switch, a reset potential VRS can be applied to the anode via a reset switch and the driving TFT. The lighting switch is turned OFF and the reset switch and the driving TFT are turned ON so that VRS is applied to the anode, before starting the application of the reference potentials to the power source lines. Following this state, the application of the reference potentials to the power source lines starts, and thus a normal operation of allowing the OLED to emit light starts.