The method for manufacturing a housing of a numeric display have the steps of: providing a first injection-molding step for forming a reflecting cover, wherein the reflecting cover has a plurality of pattern segment units, each pattern segment unit is defined by reflecting surfaces of the reflecting cover and has a through hole, and providing a second injection-molding step for forming a transparent injection-molded body into each pattern segment unit, surfaces of the formed transparent injection-molded body being bonded to the corresponding reflecting surfaces, and the reflecting cover and the transparent injection-molded body being constructed as the housing of the numeric display.