An organic light emitting display device can include a display panel that expresses brightness based on a driving current corresponding to a data voltage, a power source unit that supplies power to the display panel, and a controller configured that outputs a mode control signal for determining a normal mode and a standby mode, drives the display panel to display a first frame for a first time period in the normal mode based on the mode control signal, and drives the display panel to display a second frame for a second time period that is longer than the first time period in the standby mode based on the mode control signal, in which the power source unit supplies a compensation voltage to at least one pixel during the standby mode for compensating a change in the data voltage in the pixel.