An organic light emitting diode (OLED) display device, which can use a non-emission surface of an encapsulation substrate to reflect light, can prevent a voltage applied to a cathode from dropping, and has improved mechanical reliability, and a method of manufacturing the same. The OLED display device includes a substrate; a first electrode disposed on the substrate; an organic layer disposed on the first electrode; a second electrode disposed on the organic layer; a conductive material layer disposed on the second electrode; a metal layer disposed on the conductive material layer; an encapsulation substrate disposed on the metal layer; and an encapsulant to combine the substrate with an encapsulation substrate.