An organic light emitting diode (OLED) display includes: a substrate; a semiconductor layer on the substrate; a gate insulating layer covering the semiconductor layer; a gate electrode formed in the gate insulating layer and overlapping the semiconductor layer; a pixel electrode formed in a pixel area over the gate insulating layer; an interlayer insulating layer covering the gate electrode and the gate insulating layer, and exposing the pixel electrode through a pixel opening; a source electrode and a drain electrode formed in the interlayer insulating layer and connected to the semiconductor layer; and a barrier rib covering the interlayer insulating layer, the source electrode, and the drain electrode, and the drain electrode contacts a side wall of the pixel opening and is connected to the pixel electrode. Such an OLED display may have an improved aperture ratio.