Wire thread insert is a new kind of inner screw thread fastener, It is a new technic which is used to reinforce or repair all types inner screw thread of tappings and enables safe and highly resistant screw fitting. Particularly adapted for soft materials, Wire thread insert presents a high resistance to thermal, corrosive and mechanical strain. It is specially made of high intensity, high precision, smooth surface, cold roll and rhombic stainless steel wire, then it is formed to helical wire, it is a concentric object for inner and outer screw thread. Wire thread insert has been assembled to be a high precision inner screw thread according to the relative standard, its varied capability is much better than the inner screw thread which is directly formed by thread wimble.