In a liquid crystal display device, a drive unit is controlled in a direction of eliminating a polarity bias of a data voltage corresponding to image data at a point of time when a refresh signal for updating an image displayed on a display unit by periodical refreshment or forced refreshment is generated, and the polarity bias is obtained for each of subsequent frame periods. In this manner, not only the polarity bias after the point of time when the refresh signal is generated is obtained so that the polarity bias at the point of time when the refresh signal is generated is eliminated, but also the polarity bias is repeatedly obtained in the same way every time the refresh signal is generated, and accordingly, the polarity bias can be prevented from being increased.