Using the tissue separation method, 32 endophytic bacteria were isolated from the roots, stems and leaves of Inula helenium L., and antibacterial activiy of these strains were determined by using the agar disc diffusion test. Identification of these strains was determined by their morphological, physiological-biochemical properties and phylogenetic analysis based on 16S rRNA sequences. The results showed that the 10 endophytic bacteria had remarkable antibacterial activities to Escherichia coli, Bacillus subtilis and Pasteurella multocida. The endophytic strains YIR-5, YIR-7, YIR-8 and YIR-9 were classified as genus Pseudomonas, strains YIR-3 and YIR-6 as Serratia plymuthica, strains YIR-4, YIS-1 and YIS-2 as Rahnella aquatilis, Bacillus halotolerans and Bacillus cereus respectively, and the strain YIL-3 as the genus Bacillus. There are a variety of endophytic bacteria from Inula helenium L., and Bacillus mojavensis YIS-1 has the greatest antibacterial activity for escherichia coli, bacillus subtilis, and avian pasteurella multocida.