A cover glass includes: a flat portion disposed on a display panel which is curved and displays an image; and curved portions respectively extending from opposing ends of the flat portion. A virtual straight line is defined perpendicular to the flat portion, end surfaces of the curved portions respectively form an angle of about 90 degrees to 180 degrees with respect to the virtual straight line, and the curved portions forming the angle of about 90 degrees to 180 degrees with respect to the virtual straight line include end portions of a preliminary cover glass which are bent by engagement of a lower mold with an upper mold having the preliminary cover glass disposed therebetween