Diamond die is a wire drawing tool applied in the production of soft wire products such as copper and aluminum wires, and hard wire products such as stainless steel, tungsten and copper plated steel wires. The main production principle of wire drawing is that the wire is drawn from the big aperture through a small aperture by the hole of the diamond die and utilizes the wire's extensibility, reducing radually the circumference. The surface of the wire is also raised to its slick level during the production process.