Based on the knowledge of polymer analysis, mold design and precision machining, we utilize mold flow simulation software to conduct finite element analysis of simulation results of the effects of various necessary processes, such as packing, cooling and warping, to the structure of a mold, and to detect and check the best symmetry and balance point of pressure distribution at the end of the mold flow. The method is applied in design of extrusion dies and analysis of co-extrusion and blown film manufacturing processes, to help enhance functionality of films, promote the integration of new & old equipment and technologies, improve client's film quality and output, and reduce plastic waste and energy consumption.