To provide a friction winding shaft in which a plurality of winding cores can be accurately and reliably held at predetermined mutual intervals so as not to cause centrifugal whirling even when each winding core is the one having relatively low mechanical strength and a narrow width such as a paper tube and a synthetic resin tube and attaching/detaching operation of the winding core can be performed relatively easily and in a short time.

A plurality of winding cores C are mounted on an outer periphery of a center drive shaft 2 via a winding core adapter 3 for each winding core. The winding core adapter 3, an annular body 6 externally fitted with a center drive shaft 2, a collar 7 provided at one end part of the annular body 6, winding core fixing means 8 for fixing the winding core C externally fitted with the annular body 6 on the annular body 6, an annular groove 9 concentrically formed with the annular body 6 on one edge surface of the annular body 6, and a plurality of balls 10 accommodated in the annular groove 9 are provided. The annular bodies 6 of the winding adapters 3 whose winding adapter groups 4 are adjacent to each other are in contact with each other sandwiching the respective balls 10.