An organic light emitting display device (200, 300, 400) comprising: three emission parts (210, 220, 230; 310, 320, 330; 410, 420, 430) stacked between an anode (202, 302, 402) and a cathode (204, 304, 404), each emission part (210, 220, 230; 310, 320, 330; 410, 420, 430) comprising a hole transporting layer (212, 222, 232; 312, 322, 332; 412, 422, 432) and an electron transporting layer (216, 226, 236; 316, 326, 336; 416, 426, 436); wherein one (220; 310; 430) of the three emission parts (210, 220, 230; 310, 320, 330; 410, 420, 430) further includes at least three emission layers (223, 224, 225; 313, 314, 315; 433, 434, 435), wherein the at least three emission layers (223, 224, 225; 313, 314, 315; 433, 434, 435) are stacked one on the other; and the at least three emission layers (223, 224, 225; 313, 314, 315; 433, 434, 435) include a green emission layer (224, 225; 314, 315; 434, 435) comprising a phosphorescent material for emitting green light; a red emission layer (223; 313; 433); and a yellow-green emission layer (225, 224; 315, 314; 435, 434), wherein the red emission layer (223; 313; 433) is disposed adjacent to the yellow-green emission layer (225, 224; 315, 314; 435, 434) or to the green emission layer (224, 225; 314, 315; 434, 435) and the red emission layer (223; 313; 433) is closer to the anode than the yellow-green emission layer (225, 224; 315, 314; 435, 434) and the green emission layer (224, 225; 314, 315; 434, 435); wherein each of the remaining two emission parts (210, 230; 320, 330; 410, 420) comprises only one emission layer (214, 234; 324, 334; 414, 424) for emitting light; the emission layers of the remaining two emission parts emit light of a same color; and the one emission layer (214, 234; 324, 334; 414, 424) is one of a blue emission layer, a deep blue emission layer and a sky blue emission layer. three emission parts (210, 220, 230; 310, 320, 330; 410, 420, 430) stacked between an anode (202, 302, 402) and a cathode (204, 304, 404), each emission part (210, 220, 230; 310, 320, 330; 410, 420, 430) comprising a hole transporting layer (212, 222, 232; 312, 322, 332; 412, 422, 432) and an electron transporting layer (216, 226, 236; 316, 326, 336; 416, 426, 436); wherein one (220; 310; 430) of the three emission parts (210, 220, 230; 310, 320, 330; 410, 420, 430) further includes at least three emission layers (223, 224, 225; 313, 314, 315; 433, 434, 435), wherein the at least three emission layers (223, 224, 225; 313, 314, 315; 433, 434, 435) are stacked one on the other; and the at least three emission layers (223, 224, 225; 313, 314, 315; 433, 434, 435) include a green emission layer (224, 225; 314, 315; 434, 435) comprising a phosphorescent material for emitting green light; a red emission layer (223; 313; 433); and a yellow-green emission layer (225, 224; 315, 314; 435, 434), wherein the red emission layer (223; 313; 433) is disposed adjacent to the yellow-green emission layer (225, 224; 315, 314; 435, 434) or to the green emission layer (224, 225; 314, 315; 434, 435) and the red emission layer (223; 313; 433) is closer to the anode than the yellow-green emission layer (225, 224; 315, 314; 435, 434) and the green emission layer (224, 225; 314, 315; 434, 435); wherein each of the remaining two emission parts (210, 230; 320, 330; 410, 420) comprises only one emission layer (214, 234; 324, 334; 414, 424) for emitting light; the emission layers of the remaining two emission parts emit light of a same color; and the one emission layer (214, 234; 324, 334; 414, 424) is one of a blue emission layer, a deep blue emission layer and a sky blue emission layer.