Illumination of blue light on the newborn has an effect: First, can treat jaundice, through the light – oxygen action, the fat-soluble bilirubin into water-soluble bilirubin, so that the jaundice deposited in the skin, as soon as possible, through the stool out of the body, so that the jaundice subsides. During phototherapy, the baby needs to sleep alone on the hard board of the warming box, lacking the mother’s caress, easy to be restless. Third, the mother and baby are separated during phototherapy, and the breastfeeding method has been changed from direct sucking of breast milk to bottle-feeding, which is often prone to reduce the baby’s appetite and even lead to indigestion. Fourth, during phototherapy, fever, rash, diarrhea may occasionally occur. Parents need to be well prepared before phototherapy to avoid adverse reactions.