The indicator of neonatal jaundice is the value of serum bilirubin as a reference indicator, as long as the value of serum bilirubin does not exceed 12 mg/dl for full-term babies and 15 mg/dl for preterm babies, so as long as the value of serum bilirubin does not exceed 12 mg/dl at the time of the baby’s full-term birth is within the normal range. Many newborn babies will have mild jaundice the day after birth, which will then reach its worst, but will begin to fade gradually within a week or so. This condition is usually physiological jaundice. Even though the skin looks yellow, the serum bilirubin test is within the normal range. After one week, if the jaundice has not completely disappeared and the serum bilirubin value exceeds 12 mg/dl, the jaundice is pathological and needs to be treated promptly, otherwise it will have a great impact on the baby’s intelligence, hearing, vision and mobility. Physiological jaundice does not affect the baby’s appetite or spirit much, but in pathological jaundice, the baby’s skin is not only yellow, but also usually cries and does not eat milk. Therefore, when parents find that their newborn’s skin is yellow, it is best to have a serum bilirubin test to rule out the possibility of pathological jaundice, and prompt treatment is needed if pathological jaundice is diagnosed.