To facilitate the exchange, disassembly and inspection of a rolling bearing for supporting a driving shaft and to realize the integral structure of the driving shaft and coupling in a driving device of a rolling roll.

In the driving device of the rolling roll having one driving shaft which is flexible in the axial direction on one side, the other driving shaft which is connected to this driving shaft through a universal joint on the other side, a coupling which is provided in an end part of the driving shaft on the other side and connected to a roll neck, the rolling bearing which is arranged on the other driving shaft and with which this driving shaft is supported in the radial direction and axial direction and a carrier with which the rolling bearing is supported, the rolling bearing 5 is constituted of at least an inner race 6, an outer race 7 and rolling bodies 8 which are interposed between the inner and outer races 6, 7 and held with a retainer 9, and the inner race 6, the outer race 7 and the retainer 9 are respectively divided into plural pieces and the driving shaft 2 on the other side and the coupling 3 are integrally formed.