Abstract: In vitro separately simulated infant gastric and intestinal model and stomach- subsequent- intestine model were established in this paper,with adult conditions as comparison. In order to evaluate the oxidative stability of liposomes during simulated digestion,the proxide value and the concentration of thiobarbituric acid reaction substances were determined. Separation digestion results demonstrated that liposomes were stable during digestion in simulated gastric environment,while they were susceptible to be oxidized in simulated intestinal environment.In stomach- subsequent- intestine study,liposomes were less affected by oxygen,low p H and enzyme.However,more peroxides were formed and more severe disruption of liposomes were detected under adult conditions due to the higher concentration of pancreatic enzymes and bile salts in the adult than those in the infant environment.