The present invention provides an image display device capable of freely changing a scanning direction of an image display medium including support plates, first and second electrode groups provided at the plates and colored particles provided between the plates, including first and second electrode-driving components which receive electrode-designation signals and apply voltages to the designated electrodes in the first and second electrode groups, and which can apply voltage to plural electrodes simultaneously, a line-image-data generation component which generates line-image-data for line images to be displayed along scan electrodes in accordance with a scanning direction, and a signal-output-destination-switching component, in accordance with the scanning direction, which outputs a first electrode designation signal for designating a scan electrode of a line image and a second electrode designation signal for designating an electrode to be driven for displaying the line image, to the first electrode driving component or the second electrode driving component.