A display device includes a window panel having a first radius of curvature, a display panel and an adhesion layer. The display panel defines a first portion having a second radius of curvature, and a second portion which extends from an end of the first portion and has a third radius of curvature different from the second radius of curvature. In a line normal to the upper surface of the display panel, a first distance between a first point at the upper surface of the first portion of the display panel and a first crossing point at an upper surface of the window panel, is different from a second distance between a second point at the upper surface of the second portion of the display panel and a second crossing point at the upper surface of the window panel.