A method of detaching two plates adhered via an adhesive sheet or a curable resin layer, comprising moving, relatively parallel to each other, said two plates to develop a shear stress causing rupture of said adhesive sheet or curable resin layer. According to the present invention, two plates bonded via an adhesive sheet or a curable resin layer can be detached by only moving the two plates relatively parallel to each other. Therefore, even when at least one of the two plates is thin and poor in flexibility, two plates can be detached from each other substantially without a force (load) which causes high distortion (deformation) producing a breakage or crack on the plates. Accordingly, for example, when two optical plates adhered via a transparent adhesive sheet need to be re-bonded, two optical plates can be detached from each other and adhered again. Thus, the production cost of equipment with a display function, which carries a flat-panel display, can be reduced.