A display device includes an auxiliary electrode in order to prevent uneven brightness by the voltage drop. The display device further includes an under-cut region formed by stacked insulating layers. In the display device, the under-cut region is completely filled by filler due to changing a shape of the auxiliary electrode, so that the quality of the displaying image is improved. Also, in the display device, the contact area between an upper electrode of a light-emitting structure and the auxiliary electrode is increased, so that the reliability and the degree of integration are improved.