A hand railing includes a metal rod, a plurality of positioning units and a plastic cover. The positioning units are adapted to be secured on the surface of the metal rod. The metal rod is then placed in the injection mold, and the positioning unit is disposed between the metal rod and injection mold. The melted plastic cover is then introduced into the mold to fill the mold including the recessed portions and melt the surface of the positioning unit, so the plastic cover can completely cover the metal rod and the positioning unit. Furthermore, since the melted plastic cover also flows into recessed slot, the engagement between the metal rod and plastic cover is even stronger.