A precise torque closed-loop control method based on torque estimator for interior permanent magnet synchronous motor (IPMSM) was presented to improve the torque precision. MRAI (Model Reference Adaptive Identification) method of the IPMSM, which is based on the theory of Popov stability, was derived and analyzed. In order to improve the response speed of the system, the method of pole placement is was proposed and adopted. The effect of the adaptive model’s control parameters on MRAI’s system response speed was researched. The validation and theoretical analysis were carried out in this study. The simulation and experimental results show that the permanent magnet flux and the stator resistance could be identified accurately; the actual torque can be estimated by torque observer according to the result of parameter identification. So base on this and the torque command, the torque closed-loop control system was built the torque command. Therefore, the torque control precision of the driving system could be improved even the permanent magnet flux is changed, at the same time, the driving performance of EV is fulfilled and guaranteed.