The invention discloses a machining technology of cotton fiber and metal wire blended yarn, and relates to the technical field of blended yarn. The technology includes the following steps of firstly, preparing metal wires; secondly, preparing cotton fiber; thirdly, conducting blending; fourthly, conducting softening, drying and sizing. The technology is simple and controllable, strict high temperature and high pressure conditions are not needed, and the prepared blended yarn has beautiful metal color and luster and is excellent in electromagnetic radiation resisting, static electricity resisting and bacteria resisting performance and is comfortable and breathable; by means of softening, drying and sizing, the color fastness and softness of the cotton fiber are improved, the roughness of textile is reduced, and elasticity and strength are rich.