The severity of jaundice can be determined based on bilirubin measurements and clinical manifestations, among other things. The total serum bilirubin of a normal adult should be between 3.4 and 17.1 μmol/L, that of a full-term newborn should not exceed 171-205 μmol/L, and that of a preterm infant should not exceed 256.5 μmol/L. The higher the measured bilirubin, the more severe the jaundice is likely to be. There are four main types of jaundice: hemolytic jaundice, which is severe and has a rapid onset and is accompanied by hemolytic reactions; hepatocellular jaundice, which is a problem with the liver’s uptake of bilirubin and its conversion; obstructive jaundice, which may be accompanied by itching of the skin; and congenital non-hemolytic jaundice, which often has a family history. In jaundice, there will be yellow staining of the skin and sclera, and the more serious the situation, the deeper the yellow staining of the skin will be, and with the aggravation of jaundice, even hepatic encephalopathy may occur, which is life-threatening. It is important to pay attention to jaundice and consult a hospital as soon as possible.