The invention provides a winding device, a tension device and a winding method. A winding device 100 which winds a wire 3 around a core 11 includes the core 11, which rotates axially and around which the wire 3 is wound; a roller 21 which rotates axially and feeds the wire 3, which is wound around the roller 21, to the core 11; and a tension device 15 which adjusts a tension of the wire 3 that issupplied to the core 11 from the roller 21. A winding shape and a winding diameter of the wire 3 wound around the roller 21 are substantially identical to a winding shape and a winding diameter of the wire 3 wound around the core 11.