To provide a method of continuously straightening a steel sheet by which productivity is improved by shortening a straightening pitch by performing straightening while continuously feeding a plurality of steel sheets to a roll straightener when straightening the steel sheet with the roll straightener by a plurality of passes.

In order to straighten two steel sheets 7a, 7b by the plurality of the passes with the roll straightener while reciprocatively conveying the sheets in a set, the conveyance of the steel sheets 7a, 7b is controlled on the basis of the thickness information of the steel sheets 7a, 7b and the detected results of stop position reference sensors 4, 5 by installing the stope position reference sensors 4, 5 on conveying tables 2, 3.