An organic light emitting diode display includes a semiconductor pattern which includes a plurality of channel regions. A first gate insulating layer is on the semiconductor pattern, a first gate conductive layer is on the first gate insulating layer, a second gate insulating layer is on the first gate conductive layer, and a second gate conductive layer is on the second gate insulating layer. The channel regions include a first channel region that overlaps the first gate conductive layer and a second channel region that does not overlap the first gate conductive layer. The first channel region and the second channel region have different doping concentrations.