Autoimmune liver diseases (AILD) are a group of liver diseases that cause liver damage as a direct result of autoimmune reactions rather than viral infections, and include three main types: autoimmune hepatitis, primary biliary cirrhosis and primary sclerosing cholangitis. The incidence of autoimmune liver disease has been increasing year by year. And patients with autoimmune liver disease are often accompanied by other autoimmune diseases, and some patients with viral hepatitis, also have a combination of autoimmune liver disease. Clinical laboratory diagnosis of AILD The clinical laboratory diagnosis of AILD should include immunoglobulin assay, liver function assay, autoantibody assay, and liver biopsy. All of these patients have significantly increased serum immunoglobulins, all may have abnormal liver function, and for patients with primary biliary cirrhosis and primary sclerosing cholangitis there is mostly an increase in bilirubin and bile acids. 1, laboratory diagnostic points of autoimmune hepatitis: the presence of blood biochemical tests and pathological evidence of hepatitis, serum alkaline phosphatase is not as pronounced as increased serum transaminases; the presence of associated autoantibodies and hypergammaglobulinemia (initially manifested mainly as elevated IgG in the serum), increased sedimentation; generally negative serological indicators of each type of hepatitis virus infection, but pay attention to the overlap with viral hepatitis. Patients have a genetic predisposition to express HLA-B8, DR3 or DR4 antigens; symptoms are reduced after immunosuppressive therapy, and drug-related liver disease, alcoholic liver disease, metabolic liver disease, and PBC and PSC should be excluded, but attention should be paid to their overlapping syndromes. Autoantibodies are of great importance for the diagnosis of AIH. 2. Laboratory diagnostic points of primary biliary cirrhosis: the presence of multinuclear dot-type antinuclear antibodies SP100, gp210, LKM-1 antibodies, and AMA antibodies, with AMA antibodies being the most important feature, and high titers of AMA-M2 autoantibodies usually have important diagnostic value; likewise the presence of hypergammaglobulinemia; in addition, serum cholesterol and lipoproteins, serum binding In addition, increased concentrations of serum cholesterol and lipoproteins, serum binding protein and serum bilirubin, and increased angiotensin-converting enzyme activity are all characteristic of this disease. 3, Laboratory diagnostic points of primary sclerosing cholangitis: hypergammaglobulinemia, IgM is predominant in adult patients, but IgG is mostly elevated in pediatric patients. The presence of anti-soluble liver antigen SLA is characteristic. The patient’s CIC, C3, C4, liver enzyme profile and bilirubin are generally elevated. The diagnosis of this disease requires the exclusion of other biliary tract diseases (e.g. gallstones). Autoimmune liver disease is receiving increasing clinical attention. These diseases can also be complicated by overlapping viral hepatitis, and some serologic indicators of viral infection may mask pre-existing autoimmune liver disease. Therefore, laboratory diagnosis of autoimmune liver disease should be performed in some patients with chronic liver disease who have chronic abnormal liver function and elevated immunoglobulins (especially effective for immunosuppressive therapy). Among them, ANA, SMA, and LKM are most commonly used for early diagnosis and timely treatment. Laboratory diagnosis of autoimmune liver disease provides an effective, non-invasive diagnostic method for early diagnosis, but liver biopsy remains the confirmatory tool for this type of disease, and the laboratory screening method, known as pre-biopsy diagnosis, is currently the primary screening test. Any patient with a laboratory diagnosis of autoimmune liver disease is recommended to undergo a liver biopsy before formally entering clinical care to avoid possible misdiagnosis.