Abstract: Objective To study the clinical significance of liver failure staging in predicting the prognosis of HBV-acute-on-chronic liver failure (HBV-ACLF). Methods Four hundred and twenty-two HBV-ACLF patients admitted to our hospital from June 2009 to April 2011 were divided into early stage group (n=183), middle stage group (n=133) and end stage group (n=106). Their survival rates were analyzed. Results The mortality of the 3 groups at 4th week and 24th week was 18.58%, 24.81%, 79.25% and 33.33%, 45.11%, 84.91%, respectively, according to their prothrombin activity (PA) and complications at admission. The mortality of 199 end stage patients at 24th week was 88.44% according to the severity of HBV-ACLF in hospital stay time. The mortality at week 24 was significantly different in 5 groups divided according to the end-stage liver disease model. However, the mortality was not proportional to the end-stage liver disease model. Conclusion Liver failure staging can accurately predict the mortality in HBV-ACLF patients.