Liver function test is to monitor the indicators related to liver function and metabolism through various biochemical experimental methods to reflect the basic condition of liver function. The main purposes of liver function tests are: ① to assist in the diagnosis of various liver diseases, such as acute and chronic hepatitis, cirrhosis, hepatocellular carcinoma, etc.; ② to determine the severity, regression and prognosis of liver disease; ③ to assist in the identification of jaundice, to determine the nature and cause of jaundice, and to determine its treatment; ④ to understand the changes in the interstitial matrix of the liver; ⑤ to diagnose or confirm the special etiology of liver disease; ⑥ to understand the systemic diseases such as infectious diseases, parasitic diseases, cardiac, renal, systemic diseases, such as infectious diseases, parasitic diseases, cardiac, renal, gastrointestinal, endocrine metabolic diseases, etc. on the liver invasion or impact; (7) to understand a variety of physical and chemical factors (including drugs and industrial poisons) on the liver damage; (8) to determine a variety of Chinese and Western medicines and other therapeutic efficacy on liver diseases, or on the liver function; (9) to determine the liver function prior to the operation, which will help to estimate the likelihood of the operation and make good pre-operative preparations.