As the core of electric vehicle, the driving motor should have the advantages of high-power density, wide speed range and small volume. Aiming at the demand of vehicle drive motor and the structural characteristics of permanent magnet synchronous motor, by using Motor Cad, a internal rotor permanent magnet synchronous motor (PMSM) was designed and analysed in detail in this paper. In order to improve the anti-demagnetization ability and power density of the motor, the rotor structure was designed as a built-in compound type. At the same time, 8 poles and pear shape stator slot were adopted to reduce the loss of the motor and improve the efficiency of the motor. The simulation model of the motor was established by the simulation software, and its various performances were analysed. The simulation results showed that the design parameters of the prototype fully meet the design requirements of vehicle motor.