A display device includes a thin-film transistor, an interlayer insulating layer on the thin-film transistor, a source electrode, a drain electrode, and an auxiliary electrode on the interlayer insulating layer, each of the source electrode, the drain electrode, and the auxiliary electrode including a main conductive layer and a sub conductive layer on the main conductive layer, and a via insulating layer on the source electrode, the drain electrode and the auxiliary electrode, the via insulating layer covering the source electrode and the drain electrode and exposing a portion of an upper surface of the second conductive layer of the auxiliary electrode. The via insulating layer includes a first part spaced apart from the upper surface of the second conductive layer of the auxiliary electrode, and the second part adjacent to side surfaces of the main conductive layer and the sub conductive layer of the auxiliary electrode.