A new driving method of a display device that makes it possible to reduce power consumption and to improve display quality is proposed. A first gray scale is displayed in all pixels in a first initialization period, a second gray scale is displayed in all the pixels in a second initialization period, an objective image is displayed in a writing period, and the image is held in a holding period. Alternatively, an electrical history of a gray scale storage display element for displaying a number of gray scales is erased in the first initialization period and the second initialization period. Alternatively, a potential of a common electrode is changed in the first initialization period, the second initialization period, the writing period, and the holding period. Alternatively, a potential of a capacitor wiring is changed in synchronization with the potential of the common electrode.