The present invention realizes a liquid crystal display device which can be driven with a low voltage while preventing the degradation of liquid crystal by reducing a residual charge of a pixel electrode even when a drive circuit is abnormally stopped. As a field effect transistor which is formed on a pixel, a field effect transistor in a depletion mode which is turned on in a state that an OFF signal is not applied to a gate terminal of the transistor is used. A substrate voltage supply line which supplies a substrate voltage to pixel regions is provided, and the substrate voltage is supplied via a through hole formed in the pixel portion thus controlling an optimum threshold value in response to an input signal. Wiring is made in a peripheral portion of a display region such that video signal lines and the substrate voltage supply line intersect each other.