High jaundice is when the bilirubin level in the baby’s body is above normal. It can be physiological in newborns, a manifestation of disease in small infants, or breast milk jaundice. Jaundice in the neonatal period can be a normal phenomenon, especially in the early neonatal period when each child will have varying degrees of jaundice due to increased sources of bilirubin, giving the newborn a yellow color on the skin and sclera and other parts of the body, disappearing within 2 weeks in full-term babies and within one month in premature babies. However, it is also important to know that not all jaundice in the neonatal period is normal. Some children have poor liver function, viral infections, infections, improper feeding, hematomas, etc., which may cause high jaundice levels or jaundice that lasts too long, and for these children the cause needs to be actively sought. There is another type of child who eats and sleeps well, but the jaundice persists because of the low vitamin D3 content in breast milk during breastfeeding. For this type of child, it is necessary to ask the doctor to rule out other possible diseases. In conclusion, high jaundice can be normal in the neonatal period, or it can be a sign of disease.