Bilirubin refers to the components produced by the metabolism of the liver after the destruction of red blood cells in the body, and its clinical testing usually includes three indicators: total bilirubin, direct bilirubin and indirect bilirubin. Indirect bilirubin is a metabolic product of human red blood cells, which needs to be metabolized in the liver and combined with protein in the liver to form direct bilirubin. If the liver becomes diseased, the ability to convert indirect bilirubin into direct bilirubin is reduced, which is manifested as an increase in indirect bilirubin, and the direct bilirubin is difficult to be completely excreted from the body, which can also lead to an increase in the level of direct bilirubin in the body. Since total bilirubin is composed of direct bilirubin and indirect bilirubin, the level of total bilirubin is also elevated. Therefore, if direct bilirubin is mainly elevated, surgical obstructive lesions, such as biliary stones, biliary tumors, and biliary obstructive lesions, are mostly considered. If indirect bilirubin is predominantly elevated, medical pathologies such as megaloblastic anemia, hemolysis, hepatocellular jaundice, hepatitis, etc. should be considered. Clinically, we need to take targeted treatment measures according to different diseases, but in theory, we can all consider the application of liver-protective and anti-yellowing drugs, and patients with primary hepatocellular carcinoma need timely surgical treatment.