In order to be easily able to bundle a plurality of electric wires, an electric wire bundle comprises an electric wire group and a bundled section. The electric wire group includes a bundle in which at least some of the plurality of electric wires are bundled in the extension direction thereof. The bundled section is formed by curing a bundled section-forming material that is in a fluid form and has been linearly supplied to the outer circumferential section of the bundle in a state in which the bundle can be supported in a bundled state. This kind of bundle can be formed by discharging the fluid bundled section-forming material from a nozzle, around a bundle of a plurality of electric wires supported by the electric wire supporting section, and by curing this fluid bundled section-forming material.