PURPOSE: To improve the durability and operating efficiency of a roll by preventing the generation of roll defects and dispersing the roll defects, by shifting the roll in its axial direction through the rollings of rollers in case shifting the roll.

CONSTITUTION: When a shifting cylinder 12 is contracted, a holding frame 8 for holding a roll chock 7 is moved through the rolling of a roller 9 on the upper surface of a cam rail 10. A leveling roll 2 is shifted in its axial direction along the shape of the rail 10 while describing a circular arcuate curve, because the upper surface of rail 10 is formed into said curve. Accordingly, the generation of scratch is prevented because the roll 2 is separated from the roll 3. By performing such operation properly at every pass, the wear and roll mark generating in the roll 2 are dispersed in its axial direction, then the durability of roll is improved and the frequency of roll replacement is reduced.