To reveal the effect of white spot syndrom virus (WSSV) infection on the intestinal flora of crayfish (Procambarus clarkii),16S highthroughput sequencing technology was used to analyze the composition and diversity of the intestinal flora of crayfish in the healthy and artificialinfected group.The results showed that there was no significant difference in intestinal abundance and diversity between the WSSV infected group and the control group,but the composition of their dominant flora was different.The dominant bacteria in the control group were Proteobacteria (75.42%) and Tenericute (19.17%).The dominant intestinal bacteria in the infection group were Proteobacteria (78.14% ) and Bacteroidetes (17.38%).LEfSe analysis showed that compared with the control group,the abundance of Candidatus bacilloplasma was significantly reduced (P ＜0.05) in the infected group,and the abundance of Bacteroidaceae and Flavobacteria was significantly increased (P＜0.05).In addition,the abundance of some potential pathogens such as Flavobacterium and Aeromonas increased significantly after infection (P＜0.05).These results indicated that WSSV infection caused changes in the intestinal flora of crayfish,suggesting that WSSV may cause disease by altered the homeostatic balance of the crayfish intestine.