Neonatal jaundice is a sign of elevated levels of bilirubin in the blood, mainly due to high levels of unconjugated bilirubin in the body, or obstruction of conjugated bilirubin elimination. Bilirubin is divided into bound and unconjugated bilirubin. Most bilirubin comes from senescent red blood cells, and at this time it is unconjugated bilirubin, which needs to be bound to albumin and transported to the liver, where it is processed to become conjugated bilirubin, and then excreted into the intestinal tract via the bile. In newborns, the life span of red blood cells is relatively short, which produces too much unconjugated bilirubin from the source; the albumin of newborns is also low, which means there are fewer carriers to transport bilirubin, so the remaining unconjugated bilirubin will be high; moreover, the ability of liver cells to process bilirubin is poor, so less unconjugated bilirubin is converted into conjugated bilirubin, and for the combination of the reasons mentioned above, the unconjugated bilirubin is naturally high. As mentioned above, unconjugated bilirubin is processed by the liver to become conjugated bilirubin, and the bile secreted by the liver has to pass through the bile ducts to the intestines. If the bile ducts are blocked, then the conjugated bilirubin will not be able to go down to the bloodstream, and the conjugated bilirubin in the bloodstream will be elevated, which is usually pathologic, and intervention is needed for treatment. Neonatal jaundice is one of the most common symptoms in newborns. In most cases, physiologic jaundice in full-term infants occurs 2-3 days after birth and peaks in 4-5 days, and is usually asymptomatic, with jaundice lasting 7-10 days. However, if jaundice persists for a long time or recurs after receding, we should be alert to pathological jaundice and recommend prompt medical treatment.