To form an annular roll by rolling an elongate product, and to prevent a flaw from occurring on the product in binding elongate products by winding a binding tape to a peripheral portion of the roll.

On a peripheral portion 14 of an annular roll 10 formed by winding a flexible elongate product 1 around a first axial core 9, a binding tape 2 is wound around a second axial core 15 extending in a tangent line of the peripheral direction to allow the portion 14 to be bound. The binding tape 2 can be glued only to itself.