An organic light emitting diode (OLED) display including: a substrate; a semiconductor layer disposed on the substrate and including a switching semiconductor layer and a driving semiconductor layer connected to the switching semiconductor layer; a first gate insulating layer disposed on the semiconductor layer; a switching gate electrode and a driving gate electrode disposed on the first gate insulating layer and respectively overlapping with the switching semiconductor layer and the driving semiconductor layer; a second gate insulating layer disposed on the switching gate electrode and the driving gate electrode; a driving voltage line configured to transmit a driving voltage and disposed on the second gate insulating layer; an interlayer insulating layer disposed on the driving voltage line and the second gate insulating layer; and a data line configured to transmit a data signal and disposed on the interlayer insulating layer.