The invention is directed to reduction of a leak current of a TFT of a pixel caused by light from a backlight or external light to improve a display quality of a liquid crystal display device. The display device of the invention includes a plurality of pixels on a first substrate, where each of the pixels includes a gate line intersecting a semiconductor layer with a gate insulation film interposed therebetween, a drain line connected to a drain region through a first contact hole and covering an upper side of the semiconductor layer extending from an intersection, and a source electrode connected to a source region through a second contact hole and covering an upper side of the semiconductor layer extending from an intersection. The device further includes a light shield layer formed under the semiconductor layer with a buffer film interposed therebetween and shielding the semiconductor layer from light.