Abstract: The crystallization behavior of a polymer is simultaneously influenced by temperature and temperature experience, but its temperature field is dependent on crystallization. A coupling analysis of cooling and crystallization process was carried out to exactly simulate the temperature field and crystallization behavior of se-mi-crystalline polymer melt. In the coupling method the result of temperature field was considered as the input of crystallization analysis and then the result of spherulites evolution was used as the input of temperature field simulation, so simulation results of the double scales, macroscopic and mesoscopic, was obtained at the same time. Because the coupling analysis has the physical background, the result of numerical simulation can be thought reasonable.