Single crystal furnace is a kind of equipment which uses graphite thermal field to melt polysilicon materials in the inert gas environment dominated by high-purity argon, and grows single crystal silicon by Czochralski method. In the process of solar single crystal silicon drawing, how to improve the speed and quality of drawing crystals and reduce the energy consumption of equipment has always been the eternal pursuit of single crystal silicon manufacturers. From the perspective of mechanical structure, this paper analyzes the decrease of crystal drawing speed and extra energy consumption caused by rising crucible in single crystal furnace. On the basis of this problem, a method for optimizing the structure of single crystal furnace with crucible rising in the process of crystal drawing was proposed, and through the finite element simulation, the thermal field of the crystal and the melt before and after the optimization of the single crystal furnace and the heater power during the crystal drawing process were analyzed. The simulation analysis shows that the optimizing single crystal furnace can not only improve the stability and speed of crystal drawing process, so as to further improve the quality and output of single crystal furnace, but can also effectively reduce the energy consumption of single crystal furnace.