An organic light-emitting display device including a substrate; a pixel in a display area of the organic light-emitting display device, the pixel being implemented by an organic light-emitting diode on the substrate; a first inclination structure surrounding the pixel; a second inclination structure at least partially surrounding the first inclination structure; and a planarization layer covering the first inclination structure and the second inclination structure and having a refractive index that is greater than a refractive index of the first inclination structure and is greater than a refractive index of the second inclination structure, wherein a height of the first inclination structure is greater than a height of the second inclination structure.