A display panel of an OLED display device includes a first pixel configured to emit first color light, a second pixel configured to emit second color light, and a third pixel configured to emit third color light. Each of the first, second and third pixels includes at least two transistors, at least one capacitor and an organic light emitting diode. At least one of at least two transistors or at least one capacitor included in the third pixel has a size different from a size of a corresponding one at least two transistors or at least one capacitor included in the first pixel or the second pixel.