Abstract: Tobacco stem particles were extracted with an aqueous solution of hydrochloric acid, acetic acid, citric acid, and sodium hexametaphosphate under 80℃ for 1 hour. Then the extraction was cooled to room temperature and neutralized to about pH 3 with sodium carbonate solution. Finally, pectin was precipitated from the extraction by addition of ethanol and decolorized with an ethanol-ammonia solution. The extraction efficiency of pectin from tobacco stem was about 12.4%. The extraction conditions were optimized with orthogonal design. Influences of preprocess of tobacco stem particles, water quality, particle size, ratio of solid material to solution, number of extraction, neutral reagent, and decolorization on extraction efficiency of pectin were also discussed.