An OLED display device which prevents a color change according to a viewing angle. The OLED display device may include a substrate defined by a first pixel, a second pixel, a third pixel and a fourth pixel; an anode electrode on the substrate; a first organic light-emitting layer for emitting a first color light; a second organic light-emitting layer for emitting a second color light; a cathode electrode formed of a semi-transparent metal material on the first or second organic light-emitting layer, wherein the first organic light-emitting layer is formed in the first pixel and the second pixel; the second organic light-emitting layer is formed in the second pixel, the third pixel and the fourth pixel; and the second pixel emits mixed light of the first color light and the second color light.