With the rapid development of photovoltaic industry, the quality requirement of silicon single crystal is increasing. Czochralski is the main method to produce single crystal silicon. The production scale of single crystal silicon can be enlarged by increasing the height of the sub-chamber in the single crystal furnace. Due to the large increase in the height of the sub-chamber and the distance between the centroid of the single crystal furnace lifting head and the rotating axis of the single crystal furnace, the overall stability of the single crystal furnace is greatly affected and the production quality of the single crystal silicon is reduced. In order to solve this problem, a reliable mechanical analysis model of single crystal furnace was established, and the dynamic response of the whole single crystal furnace was analyzed by numerical simulation method. The law of motion and the maximum swing amplitude of the bottom end of tungsten wire rope were calculated when the height of the sub-chamber was increased, which provides a basis for improving the design. The numerical simulation analysis shows that the large eccentricity of the lifting head is the main reason for the shaking of the single crystal furnace lifting system. For this reason, it is proposed to add a centroid adjustment device to the lifting head, and the control system is adjusted to ensure that the mass center of the lifting head is on the rotation axis to reduce the swing of the lifting system.