It is an object of the present invention to provide a display device where expansion of a frame portion over a substrate, which results from formation of a lead wiring over an active matrix substrate, is minimally suppressed to realize a narrow frame. According to one feature of a display device of the present invention, a chamfer portion is formed at least at an end portion of an active matrix substrate having a pixel portion of a pair of substrates disposed to be opposed to each other, and wirings (a source line, a gate line, a storage capacitor line, a leading out wiring, and the like) over the active matrix substrate are electrically connected by a common wiring formed in the chamfer portion.