Examination of L.anguillarum (6 strains：HQ010516A-1 to HQ010516A-6) which were isolated from liver of naturally infected crab (Eriocheir sinensis L. ) was conducted including the morphological characteristics, main physiological and biochemical characteristics, 16S rRNA gene sequence was detected and phylogenetic analysis was constructed. In the same time，artificial infection experiment of representative strain (HQ010516A-1) to healthy crab was conducted, the results showed corresponding pathogenicity of the strain. The tests of antibiotic sensitivity of 3 strains to used 37 antimicrobial agents showed that all strains were sensitive or high sensitive to 29 agents including cefotaxime et al. ( Diameter of the zones of inhibition was 16-40 mm)，were slight sensitive to 3 agents including cefazolin et al. ( Diameter of the zones of inhibition was 10-12 mm)，were resistant to 5 agents including penicillin G et al. ( There was no zones of inhibition).