The glass fiber used in microchannel plate fabrication must be drawn in drawing furnaces. The temperature field distribution of the drawing furnace directly affects the uniformity of the wire diameter. Owing to the lack of theoretical research on glass fiber-drawing furnaces for microchannel plate fabrication, the designed drawing furnace and performance differences are based on experience. Based on the actual structure of a drawing furnace, this study aims to develop its corresponding 3D model on the basis of the theory of heat transfer analysis and to investigate the effects of the center of the furnace core, the uniformity of the heat insulation layer, and the drawing furnace temperature uniformity on the internal temperature field. Based on the theoretical analysis results, three suggestions are given to improve the drawing furnace for making micro channel plate.