The invention belongs to the technical field of 
medicine, particularly relates to a method for preparing high-purity 
Orlistat, and more particularly relates to a method for preparing high-purity 
Orlistat by utilizing mixed 
silica gel medium-pressure 
chromatography and 
crystallization as core technologies. The specific scheme of the method comprises 
filtration, lixiviation, extraction, 
chromatography, decoloring, hydrogenation, 
crystallization and 
drying processes of 
fermentation broth. According to the invention, the method provided by the invention is adopted to prepare 
Orlistat, the total yield of Orlistat is larger than 30%, and the productivity of Orlistat can reach 1.5-3 
ton / month; and by detection of HPLC (
high performance liquid chromatography), the purity of Orlistat is above 99.5%, the single 
impurity content in Orlistat is less than 0.1% and is higher than a medicinal standard. In addition, equipment used in the method provided by the invention is common chemical equipment, thus investment is less, and used solvents can be recovered and reused, thereby greatly reducing production cost and environmental 
pollution and achieving clean production.