Liver failure can be categorized into acute liver failure, subacute liver failure and chronic liver failure, which can be diagnosed on the basis of onset symptoms, indicators and laboratory tests. Specific diagnostic criteria are as follows: 1. Acute liver failure: acute onset of disease, hepatic encephalopathy of 2nd degree or above within 2 weeks, with the following manifestations: extreme fatigue, severe gastrointestinal symptoms such as anorexia, abdominal distension, nausea, vomiting, etc.; progressive deepening of jaundice within a short period of time, with total bilirubin ≥17lμmol/L, with obvious tendency to hemorrhage and exclusion of other causes, and progressive shrinkage of the liver. 2. Subacute liver failure: acute onset of the disease, the clinical manifestations of acute liver failure in a short period of time. 3. Chronic liver failure: progressive decompensation of liver function on the basis of chronic liver disease and cirrhosis. Ascites or other manifestations of portal hypertension such as splenomegaly and abdominal wall varicose veins appear. There may be hepatic encephalopathy, elevated serum total bilirubin, markedly reduced albumin, and manifestations of coagulation dysfunction. After liver failure, we should actively protect the liver treatment, absolute bed rest, reduce physical exertion, low-protein diet, and actively cooperate with the doctor’s treatment, in order to improve the prognosis.