The present invention is for providing an image display device capable of preventing deterioration of display sharpness and contrast, and capable of improving display quality. An image display medium has a display substrate, having a first electrode, disposed on an image display surface side, a rear substrate having a plurality of second electrodes facing the display substrate, and two kinds of particle groups having different colors and charge characteristics sealed between the display substrate and the rear substrate movably between the first electrode and the second electrodes by an electric field. Before application of a display drive voltage for executing the image display, a voltage is applied to the image display medium by a voltage applying component so as to generate an electric field for moving the particle groups between the second electrodes to adjacent the second electrodes.