pathogenicity and virulence genes ofisolated from diseased Huangsha soft shelled turtle in different areas of Guangxi Zhuang Autonomous Region. An artificial infection test in Huangsha soft shelled turtle was measured on the pathogenicity of the isolated strains, including a PCR assay of detecting the bacterial strains of 6 kinds of virulence genes including . The results were as follows. Forty seven strains of pathogenic T. sinensis contained 9 kinds of bacterium virulence genotypes in all, including + ahp⁺, + ahp^–, – ahp⁺, – ahp^–, + ahp^–, – ahp⁺, – ahp⁺, – ahp⁺ and – ahp^–. Around 48.94 percent of the strains carried all the 6 kinds of virulence gene detected, and the genotype of + Act⁺ was the main virulence genotype. About 95.79 percent of the , and all of them were the virulence strains. Our results also showed that pathogenicity of was the outcome of combined action of multiple virulence genes, among which gene ahal of the isolated strains had correlated action with other virulence genes, whereas the absence of gene A. hydrophila strains to Huangsha soft shelled turtle based on the artificial infection test. Strain which caused a fatality rate at or above 50 percent in Huangsha soft shelled turtle was determined to be a particularly virulent strain, whereas the one caused a fatality rate below 50 percent was determined to be a low virulent strain. Particularly virulent strains carried at least 4 kinds of virulence genes according to our study, and at the same timegenes were both present. Low virulent strains carried only two or three virulence genes besides gene. The study found for the first time that strains which carried only or to Huangsha soft shelled turtleAlt, were prone to missing. Among all the virulent strains, the strains with different genotypes varied significantly in causing fatalities rates in Huangsha soft shelled turtle <0.01). When any virulence gene is absent, the pathogenicity of the strains with the same genotype contributing to Huangsha soft shelled turtle P<0.01), which indicates that pathogenicT. sinensis contributes significantly stronger pathogenicity to Huangsha soft shelled turtle . According to the results of this study, a PCR detection of the virulence gene could be recommended to infer whether a strain is virulent or not, and the co-existence of virulence genes, , could be considered as a reasonable predictor of the particularly virulent strains.