An organic light-emitting display device with improved light efficiency includes a plurality of pixel electrodes each corresponding one of at least a first, second, or third pixel; a pixel-defining layer covering an edge and exposing a central portion of the pixel electrodes; an intermediate layer over the pixel electrode and including an emission layer; an opposite electrode over the intermediate layer; and a lens layer over the opposite electrode and including a plurality of condensing lenses each having a circular lower surface. An area of the portion of the pixel electrode exposed by the pixel-defining layer is A, and an area of the lower surface of the condensing lens is B. For the first pixel, a ratio B/A ranges from about 1.34 to about 2.63. For the second pixel, B/A ranges from about 1.43 to about 3.00, For the third pixel, B/A ranges from about 1.30 to about 2.43.