The invention discloses a novel multi-strand spring numerical control machine tool steel wire tension controller, which comprises a casing, a tension control assembly and a tension collection assembly, wherein the tension control assembly comprises a magnetic powder brake and a damping component, the tension collection assembly comprises a wire passing wheel and a pressure sensor, the magnetic powder brake and the signal output end of the pressure senor are respectively connected with an automatic machine tool control system, and steel wires are led out from a steel wire box arranged in the casing and then are led out of the casing through the wire passing wheel after going around an annular wire passing groove. The steel wire tension control automation can be realized in the production process, the tension of each strand of steel wire in the multi-strand spring processing process can be monitored in real time through the steel wire tension controller and a data collecting and control system, in addition, the tension control is carried out in real time, the effects that the tension of each strand of steel wire is constant, and the tension among each strand of steel wires is uniform and identical are realized, the tension can be monitored in real time through application program of a host computer, and a tension self setting system is completely realized, so the quality of multi-strand spring finished products is ensured.