A display device includes a base substrate including a first substrate and a second substrate sequentially laminated, a lower semiconductor layer disposed on at least one of the first substrate and the second substrate, a buffer layer disposed on the base substrate, an active semiconductor layer disposed on the buffer layer and including a first active layer of a first transistor and a second active layer of a second transistor, a first insulating layer disposed on the active semiconductor layer, and a first conductive layer disposed on the first insulating layer and including a first gate electrode of the first transistor and a second gate electrode of the second transistor, wherein the lower semiconductor layer overlaps the first active layer, and does not overlap the second active layer.