A display device includes a first base part, a semiconductor layer including a first semiconductor part disposed on the first base part and a second semiconductor part adjacent to a first side of the first semiconductor part in a first direction, a gate insulating layer disposed on the semiconductor layer and including a first gate insulating layer and a second gate insulating layer spaced apart from each other, and a gate conductive layer including a gate electrode disposed on the first gate insulating layer and overlapping the first semiconductor part and a first connecting electrode overlapping the second gate insulating layer and the second semiconductor part. The first connecting electrode includes a protrusion, the second gate insulating layer includes a recess, and the protrusion of the first connecting electrode overlaps the recess of the second gate insulating layer.