A thin film transistor array substrate and an organic light emitting diode (OLED) display device including the same are disclosed in which a color layer is disposed on a first substrate corresponding to a white sub-pixel and a non color filter area is included in a second substrate corresponding to the white sub-pixel, and thus, it is possible to lower an amount of reflectance of external light, increase a luminance efficiency, and reduce a power consumption of the OLED display device