It is an object to provide a liquid crystal display device and a driving method of a liquid crystal display device in each of which deterioration of an image display function can be suppressed and power consumption can be sufficiently reduced. In the liquid crystal display device, a fixed potential is input to a capacitor before a power source is turned off, so that a potential difference between electrodes of the capacitor disappears (capacitance becomes almost zero) such that electric field is not applied to liquid crystals, whereby the liquid crystals are in an initial state. When the supply of the power source is stopped after an initial-state image is displayed, unnecessary electric field is not continuously applied to the liquid crystals in an off state, whereby the liquid crystals can be in the stable initial state; therefore, the liquid crystals can be prevented from deteriorating.