Abstract: To provide basic data and theoretical guidance for the scientific use of pesticides, the effects of three kinds of pesticides on the activities of protective enzymes (SOD,CAT) and detoxifying enzymes (CarE, GST) in Ambrostoma quadriimpressum adult in vitro were studied. The enzyme solutions were prepared using Ambrostoma quadriimpressum Motsch adult. Different concentrations of imidacloprid, chlorbenzuron and abamectin were prepared, which were 0.001, 0.010, 0.100, 1.000, 10.000 mg/L. Then effects of the three kinds of pesticides on the enzymes were analyzed. The results showed that the activity of CAT was greatly inhibited by 0.010 mg/L imidacloprid solution and 0.001 mg/L chlorbenzuron, and the inhibitory rate was 49.62% and 52.11%, respectively. However, the activity of CAT was slightly inhibited by abamectin. The activity of SOD was slightly inhibited by abamectin. The activity of SOD was induced by high concentrations of imidacloprid (>0.010 mg/L). The activity of CarE was inhibited by abamectin while it was induced by imidacloprid and chlorbenzuron. The three kinds of pesticides all inhibited the activity of GST, but the imidacloprid showed the strongest inhibitory effect on GST. The results indicated that the activities of protective enzymes and the detoxifying enzymes in vitro were directly related to different kinds of pesticides, and the effects of the different type pesticides on the activities of in vitro enzymes were significantly different.