The purpose of this study is to explore the rational use of antimicrobial drugs, and prevent bacterial resistance to antibiotics through determination minimal inhibitory concentration(MIC), mutant prevention concentration(MPC)and mutant selection window(MSW)of monotherapy and double medicine antibiotics on Aeromonas punctata.Resistances of 10 antibiotics were tested via drugs sensitivity assays, 6 sensitive antimicrobial drugs with different mechanisms were screened and their MIC, MPC, selection index(SI)and MSW to Aeromonas punctata were determined respectively via single-drug and double-drug's combination by agar plate dilution method.The MIC of chloramphenicol, oxytetracycline, rifampicin, erythromycin, tetracycline hydrochloride, cephalosporins were 0.512, 0.416, 6.272, 2.048, 0.386, 0.512 μg/mL, respectively.The MPC of 6 antibiotics were 524.288, 1 277.952, 802.816, 1 024.000, 1 185.792, 10.880 μg/mL.The SI were 1 024.000, 3 072.000, 128.000, 500.000, 3 072.000, 21.250.The combination index of oxytetracycline and erythromycin, tetracycline hydrochloride and erythromycin, tetracycline hydrochloride and cephalosporins, oxytetracycline and cephalosporins, tetracycline hydrochloride and oxytetracycline, chloramphenicol and oxytetracycline, chloramphenicol and tetracycline hydrochloride, rifampicin and chloramphenicol, rifampicin and cephalosporins, rifampicin and tetracycline hydrochloride, rifampicin and oxytetracycline, erythromycin and cephalosporins were 1.000, 1.000, 1.000, 1.000, 0.834, 1.500, 1.500, 0.834, 2.000, 2.000, 1.000, 2.000, respectively.It was confirmed that the mutant selection window of A.punctata was narrowed effectively via double drug combination.The SIs declined from 128.000 and 3 072.000 to 1.000 and 1.000 after combination of rifampicin and tetracycline, so this demonstrated that combination of rifampicin and tetracycline closed the resistant mutant selection window, and inhibited effectively the resistant growth of A.punctata.