Corresponding to the interior permanent magnet synchronous motor (IPMSM) used in electric vehicle (EV), control system was designed. Based on the experts experience and motor response curve, combining the actual running state of EV, the fuzzy control rules were made. The fuzzy-PI controller was designed and embedded in the vector control system, and then the simulation was completed. A double-condition considering both speed and duty cycle was utilized to judge whether the flux-weakening control was necessary. A subsection control strategy was adopted according to the speed threshold. Finally, by the running experiment of IPMSM used in EV, it was proved that the response performance and running stability of the motor were improved, and the controllable speed range was widened. 