A cover for an electronic device includes a display window and a cover body injection molded with the display window. The display window includes a window body and at least one protruding portion projecting form the window body. The cover body includes a cover wall and ribs. The window body includes a front surface, a rear surface and a peripheral surface connecting the front surface and the rear surface. The at least one protruding portion is fixed on the peripheral surface and embedded between the cover wall and the ribs.