The abuse of antibiotics has a serious impact on the environment.It is very important to find a method to deal with the residual antibiotics in the environment.In this paper,the single factor method and multi factor method were used to test the degradation of avermectin by Bacillus subtilis and Shigella.The two strains showed good degradation of avermectin.Then,the response surface analysis of the experimental results was carried out by using box Behnken design software,and then the degradation conditions of avermectin were optimized.The optimum conditions for abamectin degradation by Bacillus subtiliswere temperature 35.43 ℃,sample loading 57.56 mL,bacterial concentration 3.85%,and the theoretical maximum degradation rate was 59.15%;The optimum conditions for the degradation of avermectin by Shigella were temperature 30.45 ℃,sample loading 60.24 mL and bacterial concentration 3.56%.At this time,the theoretical maximum degradation rate was 65.34%.The results showed that Bacillus subtilis and Shigella were excellent strains for abamectin degradation,and the determination coefficients of response surface model were more than 90%.Therefore,the model can be used to analyze the degradation effect of abamectin by microbial strains,and provide a theoretical basis for the degradation of abamectin by microbial strains in practice.