PURPOSE: To improve the yield by rolling a strip by utilizing a rigidity generated by biting the front and rear ends of the strip having no tension into a downstream side stand by an edger installed near to the downstream side stand.

CONSTITUTION: An intermediate edger 7 installed in the downstream of a looper device 3 between rolling stands 1, 2 presses edger rolls 6 against both width ends of a strip 5 to perform width screwing down. A mill close edger 8 installed in a position near to the downstream side stand 1 projects edge rolls 13 inside the guide face of said guides 10 for performing width screwing down. The width accuracy over the entire strip length is improved by a device with that composition.