To provide winding parts that can be increased in self inductance, without having to change the number of turns of a wire or to change the material of a core.

The winding parts 1 are constituted by winding the wire 3 and arranging a soft magnetic material in the gaps between the turns of the wire 3. Since the self inductance of the parts 1 can be increased, without increasing the number of turns of the wire 3 or changing the material of the core, the size of the parts 1 can be reduced. Consequently, a transformer or choke coil, using winding which has a larger self inductance can be manufactured.