An organic light emitting display capable of reducing power consumption in a standby mode and a method of driving the same. The organic light emitting display includes a pixel unit having a first emission region and a second emission region, wherein the pixel unit is configured to generate a driving current in accordance with data signals and scan signals to emit light so that light is emitted by the pixel unit only in the first emission region in a standby mode, a data driver for transmitting the data signals only to the first emission region in the standby mode, a scan driver for outputting the scan signals, and a power source supplier for generating and outputting voltages of an initialization power source and for blocking the driving current from flowing to the second emission region by utilizing a voltage of the initialization power source in the standby mode.