In order to study the design and electromagnetic heat of electric vehicle hub motor based on finite element simulation model, the electric vehicle hub motor is designed by using finite element method, and the simulation model based on finite element method is established. The maximum speed of electric vehicle, the number of poles and the temperature field are collected and analyzed to verify the operation effect of the simulation model. The results show that from the data of the start-up process, about 40ms, the speed is accelerated rapidly and it is in the exponential rising stage. Until 150ms, the speed starts to reach a stable state, and its speed reaches about 189rmp. From the point of view of the pair pole number, the power factor of the motor decreases linearly with the increase of the pair pole number; from the point of view of the temperature field, when the height of the stator yoke remains unchanged, the temperature at the highest temperature reaches stability between 25 and 30 minutes, and its stable temperature reaches 156°C. When the height of the stator yoke increases by 20mm and 30mm, the temperature curve at the highest temperature almost coincides and the stable temperature of them is 123°C. Based on the finite element simulation model, the simulation model of electric vehicle hub motor is designed. Through the verification, it basically meets the expectation, and its optimization effect runs well and meets the expectation. Although there are still some shortcomings in the research process, it can also contribute to the development of the automotive industry, and has a certain reference and guidance role for future research, which is a research subject closely following the direction of development.