An organic light emitting diode (OLED) display device which can improve emission efficiency and reduce (or minimize) resonance effect, and a method of fabricating the same. The OLED display device includes a substrate; a first electrode disposed on the substrate and including a reflective layer; an organic layer disposed on the first electrode and including a white emission layer and a hole injection layer having a thickness between 200 and 300 Å; and a second electrode disposed on the organic layer.