Total 20 strains of endophytic bacteria were isolated from different parts of Alhagi pseudalhagi Desv.for the first time by grinding method and 1 strain XJASAB11 was screened out from them with the stronggest antagonistic activity.According to the physiological and biochemical characteristics,16S rDNA sequencing analysis,the XJASAB11 was identified as Bacillus sp.The antagonistic strain was further amplification cultured and its metabolites was studied initially with column chromatography on silica gel and TLC chromatography.The active monomers C2 and H22 were obtained from the antibacterial phase.UVspectra,¹HNMR and MS results showed that compound C2 and H22 were flavoniods.The molecular formula of these compounds need to be further studied.Our study indicated that A.pseudalhagi Desv.endophytes have plenty of antimicrobial substances as a potential resources of devolopement of natural antimicrobile drugs.