PURPOSE: To reduce the cost in repair by making a coordinate by finding the wear thickness reducing quantity of a roll shell at the measuring point in the prescribed pitch, then by performing the build-up weldings of the underlaying and upperlaying as well as removing the thin film based on the coordinate thereof.

CONSTITUTION: The coordinate at respective measuring point is found by observing the wear thickness reducing quantity at the measuring point of 20W200mm pitch on the shell part 11 of the roll 10 with partial wear. The NC cutting for removing the thin film is performed so as to become in the outer diameter shape approaching to the polygonal line linking this coordinate, then. Moreover, a thin underlaying welding metal layer 14 is welded on this machined surface and the upperlaying buildup welding metal layer 15 in proportion to the wear thickness reducing quantity is formed on the surface as well. Due to the build-up layers 14, 15 of a tough hardening steel being formed on the lower layer and a surface hardening welding steel on the upper layer, the roll life is extended and the repair time can be shortened. Consequently the repair cost is reduced in this way.