Abstract: Phytosterol is a new resource food,which can effectively reduce the cholesterol content in human serum.To improve the solubility and bioavailability of phytosterols in lipids,esterification is often used to improve their hydrophobicity.The soybean sterol stearate was synthesized by chemical esterification method,and Normal-phase High Performance Liquid Chromatography was used for qualification and quantitation the products.The effect of catalyst type,molar ratio of soybean sterols to stearic acid,catalyst amount,reaction temperature and reaction time on the yield of soybean sterol stearate was investigated.On the basis of single-factor experiment,orthogonal experiment was carried out to obtain the optimum conditions for soybean sterol stearate synthesis.The optimal conditions were shown as follows:sodium hydrogen sulphate as catalyst,catalyst amount 5%(the mass of soybean sterols and stearic acid),molar ratio of soybean sterols to stearic acid 1:1.2,reaction temperature 130℃,and reaction time 8 h.Under the above optimal conditions,the yield of soybean sterol stearate was up to 95.00%,while the conversion yield of soybean sterols was 97.29%.The afforded soybean sterol stearate products were purified and characterized by Infrared Spectroscopy.High purity soybean sterol stearate products were synthesized by chemical method in this paper,which will provided technical support for the efficient production,development and utilization of phytosterol esters.