Based on the passivity theorem, an approach of the rotor resistance estimation and sliding mode position control for induction motor drives is proposed in this paper. Owing to values of the moment of inertia and the viscous coefficient of induction motors are generally small, the load torque disturbance is a critical term to create the chattering phenomenon. The adaptive laws are taken into account for estimating the rotor resistance and the gain of a load torque. Therefore, the chattering associated with the conventional sliding mode controller can be alleviated. The stability analysis of the estimator and the position control system is carried out by employing the passivity theorem. Finally, experimental results are presented to show the performance and robustness of the estimator and the controller with the variations of the motor mechanical parameters, rotor resistance, and load torque disturbances.