In direct torque control system for induction motor, the system has big torque ripple and strong noise caused by torque ripple. In indirect stator-quantities control, a slip frequency controller, based on power frequency exponent integration reaching law sliding model, is adopted by using practical measure velocity and calculation torque of motor flux model. The slip frequency error is fast convergent and stable in the nearby zero value, the method reduces torque ripple and improve dynamic and stable performance. The stability analysis of the scheme is given by using Lyapunov method. The simulation results verify the effectiveness and correctness of the method.