To constitute a rolling device for a rolling mill in such a manner that torque and the bending load during rolling operation are optimally transmitted roll replacement can be easily executed, and a component required for a rolling device, especially, a roll can be inexpensively manufactured.

A means (4) for transmitting driving torque so as to restrain a shape has a first toothed ring (5) joined relatively irrotationally with a roll shaft (2) and a second toothed ring (6) joined relatively irrotationally with the roll (3). Both of the toothed rings (5, 6) have teeth for engaging with each other so as to restrain a shape.