To provide a method and a device for winding a core body, in which in relation to a manufacturing method for a toothed belt using molten thermoplastic polyurethane, traveling life of the belt obtained by aligning, hanging and rotating a core body code is prolonged and feeding of the core body code is automatically enabled.

In the method for winding the core body code, in which the core body code 1 is spirally wound in equal intervals between a pair of belt forming molds 2, 2, freely rotary guide rolls 3 having guide groove parts 14 of equal intervals in the peripheral direction on the outer peripheral surface are provided so that the axial centers intersect the axial centers of the belt forming molds 2 at a prescribed angle. The core body code 1 is passed through the guide groove parts 14 of the guide rolls 3, hung and rotated around a pair of belt forming molds 2, 2. While giving a prescribed tension to the core body code 1, a pair of belt forming molds 2, 2 are rotated and while the core body code is automatically moved in the axial direction between the forming molds, the same is hung and rotated.