Indirect bilirubin, also known as non-conjugated bilirubin, i.e. bilirubin not combined with glucuronic acid, is mainly produced by the destruction of red blood cells through hepatic metabolism. Its concentration can reflect the transformation function of liver cells and the decomposition state of red blood cells. The normal value of indirect bilirubin in normal adults is 3.4-17.0 μmol/L, while the normal value of indirect bilirubin in newborns is 1.7-10.2 μmol/L. Therefore, indirect bilirubin 20 μmol/L is higher than the normal value. It is generally seen in some malignant diseases of the liver, such as acute jaundice, acute yellow hepatic necrosis, chronic active hepatitis, and cirrhosis. Secondly, it can be seen in hemolytic jaundice, which means that a large number of red blood cells in the body are destroyed and indirect bilirubin is released. When there is too much indirect bilirubin in the blood, it exceeds the conversion capacity of the liver, so that the indirect bilirubin stays in the blood, thus causing high indirect bilirubin in the blood. When blood of incompatible blood type is imported, it will lead to hemolysis, which will destroy a large number of red blood cells in the body, thus causing high indirect bilirubin in blood. However, indirect bilirubin 20μmol/L does not necessarily represent the disease state, it may also be caused by drinking alcohol and eating fatty food, and whether it is normal or not needs to be further clarified according to total bilirubin, hepatitis B five, blood routine, liver imaging and other related tests.