A steel rope unknotting machine comprises a tension part and a traction part, wherein one end of a motor of the tension part is fixed on a tension rack, the other end of the motor of the tension part is connected with a spindle by a coupler, the spindle is connected with a winching frame to be used as a rotary shaft of the winching frame, a steel rope disk is fixed by a shaft rod connected with the winching frame by two shaft supports and fixed by an attached iron pin, each shaft support is fixed on the winching frame by a step shaft and a bearing, the outside of the step shaft is connected with a brake disk synchronously rotating with the steel rope disk, a brake is arranged on the brake disk, a line winding device of the traction part is mounted at the tail end of a traction rack, a traction rope disk is arranged at the front end of the traction rack, and a motor is fixed on the bottom of the traction rack and is connected with the line winding device and the traction rope disk respectively by a driving mechanism. The steel rope unknotting machine has the advantages of changing the severe requirement on use occasion, reducing personnel investment, improving the work environment of an operator, solving the problem of poor torque and improving the work efficiency.