An organic light-emitting display that includes a substrate comprising a pixel area, a thin film transistor arranged within the pixel area, a wiring electrically connected to the a thin film transistor, an insulating layer covering the thin film transistor and the wiring, a pixel electrode arranged over the insulating layer, a pixel-defining layer having an opening that exposes the pixel electrode, an opposite electrode facing the pixel electrode and an organic emission layer interposed between the pixel electrode and the opposite electrode, the insulating layer having a first region that is overlapped by the pixel electrode and a second region that is not overlapped by the pixel electrode, the second region being thicker than the first region to reduce parasitic capacitance between the opposite electrode and the wiring.