An organic light-emitting display device and a method of fabricating the same. The organic light-emitting display device includes a substrate including a plurality of subpixels and an overcoat layer disposed in light-emitting areas of the plurality of subpixels. The overcoat layer includes microlenses composed of a plurality of concave portions or a plurality of convex portions. Organic electroluminescent devices are disposed on the overcoat layer. At least one subpixel of the plurality of subpixels includes first microlenses and second microlenses of the microlenses, the second microlenses being different from the first microlenses.