An organic light-emitting diode (OLED) display is disclosed. In one aspect, the display includes a display panel including a plurality of pixels, each of the pixels including an OLED and a driving transistor, the OLED configured to emit light based on an emission current, the driving transistor configured to control the emission current based on a data signal applied to a gate electrode of the driving transistor. The display also includes a power supply configured to apply a driving voltage to the pixels, apply an initialization voltage to a first electrode of the OLED, control the driving voltage within a first range, and control the initialization voltage such that a voltage difference between the driving voltage and the initialization voltage is substantially constant.