Baby jaundice may be related to excessive bilirubin production, bilirubin metabolism disorders, bilirubin excretion disorders and so on. 1. Excessive bilirubin production: due to increased destruction of red blood cells and increased enterohepatic circulation, such as erythrocytosis, intracranial or subcutaneous hemorrhage, hemolysis, and infections. 2. Bilirubin metabolism disorder: due to the low ability of hepatocytes to take up and bind bilirubin, such as asphyxia, hypoxia, acidosis, sulfonamides, hypothyroidism and so on. 3. Bilirubin excretion disorder: due to the liver cells and bile ducts to bile secretion and excretion of obstacles caused by, such as neonatal hepatitis, biliary tract obstruction and so on. Baby jaundice may have other causes, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, give targeted treatment or treatment.