A polishing apparatus for a roll, which is to be immersed in a molten metal plating bath, on which multiple grooves are formed on the circumferential surface of the roll, and which is to be used when bringing a metal band in contact with the circumferential surface of the roll in molten metal in a plating bath while continuously supplying a metal into the molten metal in the plating bath to plate the metal band. The polishing apparatus is provided with a loading means for loading a polishing means for selectively and mechanically polishing at least a portion of a non-contacting region, which does not contact the metal band and is closer to the bottom of the groove than the contacting region of the circumferential surface of the roll that contacts the metal band in the molten metal in the plating bath.
