[Objectives]  To investigate the effects of tea saponin on detoxification and protective enzyme activity of Locusta migratoria. [Methods]  The effects of different concentrations of tea saponin on the activity of glutathione-S-transferase (GST), carboxylatetasse (CarE), cytochrome P450 (CYP450), peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) were compared by injecting low, medium and high concentrations of tea saponin solution into the abdomen of adult L. migratoria and monitoring changes in detoxification and protective enzyme activity after 0, 12, 24 and 48 h. [Results]  The activity of the three detoxification enzymes increased rapidly in the low concentration treatment group, but GST activity was subsequently inhibited, and CarE activity was highest in the medium concentration treatment group. The activity of CYP450 increased with tea saponin dosage. CarE and CYP450 activity increased significantly after 12 h, and the activity of GST increased significantly after 24 h. POD and CAT had the highest activity in the low-concentration treatment group, whereas SOD activity increased significantly in the medium concentration treatment group. Protective enzyme activity began to increase significantly after 24 h in the low concentration treatment group. POD and SOD activity continued to increase, but CAT activity decreased, after 48 h. [Conclusion]  Tea saponin can affect the activity of both detoxifying and protective enzyme in Locusta migratoria.