To provide a friction winding shaft, without requiring complex accessory equipment for preventing an expansible-contractible tube for pushing up a friction lug from being collapsed by pressure of compressed air supplied to its outer periphery.

The friction winding shaft is provided so that when a belt-like sheet is wound, a pressure fluid is supplied inside the expansible-contractible tube 3 arranged in a hollow part of a central driving shaft 1, torque of the central driving shaft 1 is transmitted to a winding collar 2 by pressing the friction lug 5 to the winding collar 2 by expanding the expansible-contractible tube 3, a core C out-fitted to the winding collar 2 is fixed to the winding collar 2 by a core fixing mechanism 6, making the core C restricted by a core lateral dislocation preventive device 8, and when the core C is attached and detached, the core lateral dislocation preventive device 8 is operated by supplying the pressure fluid to the outer periphery of the expansible-contractible tube 3 and restriction of the core C by the core lateral dislocation preventive device 8 can be released. A core member 9 is stored inside the expansible-contractible tube 3.