[Problem to be Solved] To provide a helical capacitor for controlling a high-frequency power which flows in power lines, and a manufacturing method of the helical capacitor.[Solution] A helical capacitor is constituted by helically spiraling a belt shape capacitor line 1001 which includes an internal metal body to be a helically spiraled belt-shape internal electrical conductor, a dielectric film covering the internal electrical conductor, and an electrically conductive layer covering the dielectric film. The capacitor line of belt shape 1001 can be wrapped around the internal support body 1200. Internal metal body lead terminals 1311, 1321 are respectively formed at both ends of the internal metal body, and electrically conductive layer lead terminals 1312, 1322 can be respectively formed at both ends of the electrically conductive layer.