An organic light-emitting diode (OLED) display device includes a substrate; a transistor device disposed on the substrate; a first electrode electrically connected to the transistor device; an organic light-emitting layer disposed on the first electrode; and a second electrode disposed on the organic light-emitting layer. The OLED display device further includes a transflective layer contacting a lower surface of the first electrode and having a relatively higher refractive index than the first electrode.