Abstract: In order to ascertain pathotypes of Xanthomonas oryzae pv. oryzicola population and their distribution in Anhui Province, bacterial isolates were recovered from diseased leaves of rice plants associated with bacterial leaf streak located in different regions in Anhui Province using the plate dilution methods, and strains of X. oryzae pv. oryzicola were identified by PCR detection. With six differential rice varieties (IRBB5, IRBB14, IR24, IRBB4, IRBB21 and ‘Jingang30’), the virulence differentiation of X. oryzae pv. oryzicola population was identified by the inoculation methods of leaf-needling at adult stage. The results showed that a total of 72 bacterial isolates were obtained and identified as X. oryzae pv. oryzicola, and there were significant difference of virulence among these strains of X. oryzae pv. oryzicola from different regions in Anhui Province. The strains with strong virulence and weak pathogenicity existed in the population of the pathogen, and most strains were found weak interaction between bacterial strains and rice varieties, but the minority of the strains was specific interaction significantly. Six pathotypes (Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ and Ⅵ) were classified according to their virulence differences on 6 differential rice varieties. It can be concluded that the virulence difference was obvious among X. oryzae pv. oryzicola population in Anhui Province, and the virulence of X. oryzae pv. oryzicola population is relative to the origin of strains.