A truing device is supported so as to be elastically movable in the Z-axis direction, which is parallel to a grinding wheel rotational axis, and elastically movable in the X-axis direction in which a grinding wheel cuts into the truing device, and includes a movement restriction device that controls prohibition and permission of elastic movement. The method includes: causing a surface of the grinding wheel to contact the truing device in the X-axis direction; and correcting a shape of the grinding wheel when the grinding wheel cuts into the truing device until the amount of elastic movement of the truing device in the X-axis direction reaches a first predetermined amount, by controlling the movement restriction device to prohibit elastic movement of the truing device, and thereafter causing the grinding wheel to further cut into the truing device in the X-axis direction by a second predetermined amount.