Neonatal bilirubin of 300 μmol/L mostly suggests pathological jaundice, which needs to be judged comprehensively according to the postnatal age, gestational age at birth, whether there are neurological complications and the severity of the disease. Prompt consultation is needed to identify the cause of the disease and treat it promptly. Pathological jaundice can be caused by hemolytic disease of the newborn, infectious disease of the newborn, neonatal hepatitis, breastfeeding-related jaundice, extravascular hemolysis, hereditary factors, congenital diseases, etc., which need to be diagnosed by a specialist after examination and evaluation. In addition, the severity of the disease needs to be judged according to the postnatal age, the gestational age at birth, whether there are neurological complications and the severity of the disease. Continuous increase in bilirubin or maintaining a high level of bilirubin without lowering it may lead to bilirubin encephalopathy and bilirubin-induced neurological dysfunction and other complications, and even leave neurological sequelae. Neonatal bilirubin of 3000 μmol/L is usually indicative of pathological jaundice, which requires immediate medical treatment, and the severity of the disease needs to be evaluated by a specialist to determine the severity of the disease, and timely consultation is required to avoid delaying the treatment.