Abstract: Taking Hippophae rhamnoides leaf tea as test material, using the method of single factor experiment and orthogonal experiment to study the ratio of material to liquid, the effects of ultrasonic time, ultrasonic temperature and ethanol concentration on the extraction rate of polysaccharide and the lipid-lowering function of tea polysaccharide from Hippophae rhamnoides leaf in vitro were studied, in order to provide reference for comprehensive development and utilization of tea polysaccharide from hippophae rhamnoides leaf.The results showed that the optimal extraction conditions of sea buckthorn tea polysaccharide were 1∶20 g·mL^-1,60 minutes sonication time, 60 ℃ sonication temperature and 85% ethanol concentration, under which the extraction rate of sea buckthorn tea polysaccharide was（5.277±0.149）mg·g^-1.Moreover, the inhibition rates of sea buckthorn tea polysaccharide on cholesterol esterase and pancreatic lipase could reach 70% and 60%,respectively, and the dose-effect relationship was observed, indicating that sea buckthorn tea polysaccharide has certain lipid-lowering effect.