Acute-on-chronic liver failure( ACLF) is the most complicated form of liver failure among various types of liver failure. There are certain differences in the conception,etiology,and pathogenesis of ACLF between different regions. In recent years,ACLF has attracted attention of hepatologists all over the world,and some important progress has been made,which contributes to academic communication on ACLF,an early consensus on the diagnosis and treatment of ACLF,and eventually an increased survival rate in patients. This paper reviews the differences in conception between the Eastern and Western parts of the world,pathogenesis,treatment,and prognostic judgment of ACLF.