A reversible image display medium including two sheets; one or more developer accommodating cells formed between the two sheets, and each having a periphery surrounded by a partition wall; and dry developer contained in each of the cell(s), wherein the dry developer contains at least two kinds of frictionally chargeable dry developer particles having different chargeable polarities and different optical reflection densities. The image is displayed by forming a predetermined electrostatic field for each pixel in accordance with the image to be displayed and thereby moving the developer particles in a frictionally charged state. The image formed on the reversible image display medium can be erased, e.g., by an image erasing device.