Abstract: In order to screen the biocontrol strains suitable for the late blight of potato in Inner Mongolia,a strain with pathogens resistant to Phytophthora infestans was obtained from the desert soil of western Inner Mongolia.The strain was analyzed by 16S rDNA sequence and it was near Brevibacillus formosus.The results showed that the strain had good inhibitory effect on Phytophthora infestans by plate experiment,potato leaf in vitro experiment and potato tuber in vitro experiment,and had further research value.