An endophytic bacterium strain EBS05 from Cinamonum camphra was identified as Bacillus subtilis by morphological taxonomy and sequence analysis of 16S~23S rRNA intergenic spacer regions. Properties of antimicrobial compound produced by EBS05 were assayed. The active compound had the maximum absorbance peak at λ213.5 nm. The antimicrobial activity was stable in solution with pH value from 5 to 8, and decreased significantly in solution with pH value less than 4.0 or more than 9.0. The antimicrobial compound had thermodynamics stability. Its activity changed a little after treated at 60°C~80°C for two hours, and compared with 65% original activity after treated at 1×105 Pa for 30 minutes. The active substance had high resistance to ultraviolet radiation and protease K. Antimicrobial compound was soluble in alcohol solution, which was easily dissolved in methanol and ethanol, but not dissolved in ethyl acetate, acetonitrile and petroleum et al.