An organic light emitting display device including: a substrate; an organic light emitting device on the substrate to display an image; a sealing member on the organic light emitting device; a phase delay layer disposed on the substrate, the organic light emitting device, or the sealing member; a linear polarization layer disposed on the substrate, the organic light emitting device, the sealing member, or the phase delay layer and is located closer to a display surface of the organic light emitting display where the image is displayed than the organic light emitting device, the sealing member, and the phase delay layer are from the display surface; a multi-phase delay layer between the phase delay layer and the linear polarization layer; and a transmittance control layer disposed on the substrate, the organic light emitting device, the sealing member, the phase delay layer, the multi-phase delay layer, or the linear polarization layer.