Abstract: The effect of Lycium barbarum polysaccharide( LBP) on delaying fatigue via attenuating oxidative stress was studied in mice model.After 2- week LBP treatment with dose of 25,50 and 100 mg / kg,exercise time of the mice was detected via rotating rod test,forced swimming test,and forced running test.After 20 min swimming,the levels of hepatic glycogen,muscle glycogen,and some antioxidant indexes were detected in serum,liver,and muscle.LBP obviously prolonged exercise time,increased the levels of liver glycogen and muscle glycogen,enhanced the activities of SOD and GSH- Px,and decreased the levels of MDA and ROS in serum,liver and muscle.The anti- fatigue activity of LBP may be associated with attenuating oxidative,further increasing glycogen content in the mice.