Abstract: The influences of total alkaloid and its monomers from Sophora alopecuroids on the activities of digestive and protective enzymes in Clostera anastomosis were studied.Results showed that the activity of SOD was significantly higher than those of the controls and there were no effects on the activities of POD and CAT when treated with the total alkaloid or matrine for 5 hrs. As viewed from the variation trends of protective enzymes, the activities of POD and CAT after the treatment with sophoramine showed a gradual increase in prophase, a subsequent decease and an increase again in anaphase. However, the activity of SOD increased in prophase, subsequent decreased and then kept at a lower level. The variation of CAT after treatment with sophocarpine was similar to the one with sophoramine treatment. But activities of SOD and POD were not changed obviously within 21 hrs.Results also indicated that the total alkaloid had significant influences on the activities of digestive enzymes in the tested insects. In Clostera anastomosis, the activities of proteinase and amylase were significantly higher than those of the controls when treated with the total alkaloid for 24 hrs. But the effects of six alkaloid monomers on the activities digestive enzymes in the insects were slight.These results indicated that the dynamic balances among SOD, CAT and POD in Clostera anastomosis were destroyed by alkaloids from Sophora alopecuroids. It led to the free radical clear system undergoing dysfunction, the level of free radical in Clostera anastomosis increased, and consequently injured the larvae.