Abstract: In order to detect whether B. amyloliquefaciens could help plant against the infection of Pst DC3000, using petri dish and pot experiments to analyze the efficiency of B. amyloliquefaciens against the Pst DC3000 infection process in Arabidopsis thaliana. The results showed B. amyloliquefoz.ieus inhibited the growth of＇ Pst DC3000 in petri dish condition. After spayed of Pst DC3000, leaves with pre-treatment, irrigated or sprayed with B. amyloliquefoz.ieus, wilted later than control and the count of Pst DC3000 in leaves were less than control. In conclusion, B. amyloliquefoz.ieus has good inhibition efficieney against Pst DC3000 in petri dish or plants. The study provides experimental basis for further analyze the mechanism of biological control of B. amyloliquefacieus.