In order to prevent dielectric breakdown of TFT or an interlayer insulating film by static electricity with a reduced area at low cost, a liquid crystal display device has a configuration in which an interlayer insulating film and an a-Si film are formed in a display area and a control area inside terminals. Image signal lines and scan lines are insulated from each other through the interlayer insulating film and a-Si film in their intersections. On the other hand, only the interlayer insulating film is formed between static electricity protection lines and an earth line outside the terminals. When static electricity is induced, dielectric breakdown is caused to occur in the area outside the terminals. Thus, the display area and the control area are protected from the static electricity.