Abstract: The role of the Clanis bilineata Walker in the anti- fatigue was studied. 80 healthy mice were divided randomly into 5 groups ( half male and half female in each group) .Two dose of alcohol extract of C.bilineata Walker ( 6.25g/kg and 12.5g/kg) , a blank dose and a dose of Panax quinquefolius was applied to the aging model mice.The swimming and climbing time, the contents of blood urea nitrogen, blood lactic acid and liver glycogen of mice were observed.The results showed that the high dose of alcohol extract of C.bilineata Walker could significantly prolong the swimming ( p < 0.01) and climbing time ( p < 0.05) , improve the moving endurance, decrease the contents of blood urea nitrogen ( p < 0.05) and blood lactic acid ( p < 0.01) and increase the contents of hepatic glycogen ( p < 0.01) after exercise.The low dose of alcohol extract of C.bilineata Walker also had some effect on those indicators, but was not as significant as the high concentration. C. bilineata Walker. It's concluded that C.bilineate walker had the function of alleviating physical fatigue.