An organic light emitting diode (OLED) display device is provided. The OLED device includes a substrate, a first light emitting unit and a second light emitting unit. The first light emitting unit is disposed on the substrate. The first light emitting unit includes a first organic light emitting layer, a second organic light emitting layer and a first charge generation unit. The first charge generation unit is located between the first organic light emitting layer and the second organic light emitting layer. The first organic light emitting layer and the second organic light emitting layer are respectively in contact with a top surface and a bottom surface of the first charge generation unit. The second light emitting unit is disposed on the substrate. The second light emitting unit includes a third organic light emitting layer, and the second light emitting unit does not include a charge generation unit.