PURPOSE: To shorten the time of preparation by providing a clutch and a driving shaft contracting means at the prescribed driving shaft among plural driving shafts.

CONSTITUTION: A clutch 6 to shut off the torque transmission from the driving part is provided between a universal joint 32 of one hand driving shaft 3 and a driving side shaft body 34. And a driving shaft contracting means 7 for contracting this driving shaft 3 to the axial direction is provided, and the interference of the driving shaft with a small diameter work roll can be prevented. Therefore, the rolling mill can be used as the CR mill(CLUSTER TIPE ROLL ING MILL), without detaching the driving shaft from the driving device.