HBV is the cause of acute-on-chronic liver failure in most patients,and therefore,acute-on-chronic hepatitis B liver failure is one ofthe most challenging public health issues at present.Long-term administration of nucleos (t) ide analogues,abuse of various drugs,and change in drinking habits caused by economic and cultural diversity contribute to the complex predisposing factors for acute-on -chronic hepatitis B liver failure.An analysis of these reasons can help to prevent the development of acute-on-chronic hepatitis B liver failure in the early stage and reduce mortality rate.