Generally speaking, physiological and pathological jaundice can be judged from the time of occurrence, etiology and mental status. 1. Occurrence time: physiologic jaundice occurs later, usually 3-4 days after birth, while pathologic jaundice may occur earlier, less than 24 hours after birth, or even within 48 hours, a relatively high level of jaundice can occur. 2. Etiology: Physiologic jaundice is mainly affected by three major factors, which are high bilirubin concentration, immature liver function and immature liver and intestinal circulation. Pathological jaundice has more causes, and the common ones are neonatal infection, biliary malformation, hypoxia, biliary atresia, acidosis, inborn genetic metabolic disease, bilirubin excretion disorder, and intestinal and hepatic circulation abnormality. 3. mental state: physiological jaundice baby’s mental state is relatively good, will not appear abnormal conditions, but jaundice, can if it is pathologic jaundice, the mental state is often not very good, and even prone to shrieking, convulsions and so on. If the child has physiological jaundice or pathological through the above way to determine, such as abnormalities, it is recommended to seek medical attention in a timely manner, after a clear examination, and actively cooperate with the doctor for treatment.