There is provided a flexible display device including a display panel for displaying an image, and a window substrate covering the touch screen panel, the widow substrate including a flexible base layer including an externally facing first surface, and a second surface opposite the first surface and facing the display panel, a hard coating layer having a hardness that is larger than that of the base layer, and including a plurality of coating tiles on the first surface of the base layer that are spaced to have a gap between adjacent ones of the coating tiles, and a self-healing coating layer including a self-healing material and covering the hard coating layer on the base layer.