Abstract: A plurality of centering parts 13 corresponding to drill diameters are disposed in a drill centering tool 3 and the drill centering tool 3 is supported at the side of a drill polishing machine 1. A drill 2 to be polished can be easily and accurately centered in the centering part 13 of the drill centering tool 3. In particular, the drill 2 is centered by fitting the front end portion of the spiral drill groove 14 of the drill 2 to a centering pawl 15 of the drill centering tool 3, chucking the centered drill 2 in a drill chuck 4 of the drill polishing machine 1, and polishing by fitting the cutting edge 5 to be polished at the front end of the drill 2 to the polishing surface of a grinder. Even if the drill diameters are different, drills to be polished can be easily centered and polished.