A display device includes: a first substrate; a poly-silicon layer disposed on the first substrate; a first metal layer disposed on the poly-silicon layer and including a gate electrode; a first insulating layer disposed on the first metal layer; a second insulating layer disposed on the first insulating layer; a second metal layer covering a part of the second insulating layer; and a light emitting diode unit electrically connected to a first portion of the second metal layer, wherein a thickness of the second insulating layer under the second metal layer is larger than a thickness of the second insulating layer uncovered with the second metal layer.