Blue light can be used to treat jaundice, but it is not effective in all cases of jaundice. Blue light therapy is clinically indicated mainly for pathological jaundice in newborns, such as hemolytic jaundice, with good clinical results and relatively few side effects. It converts the indirect bilirubin in the blood, which is excreted through the urine. However, care should also be taken to cover the genitals as well as the eyes during blue light irradiation to avoid damage. During the process of blue light exposure, attention should also be paid to hydration, trace elements and skin care. The duration of blue light irradiation also depends on the severity of the jaundice, but the combination of blue light irradiation and other treatment options is often used to treat neonatal pathological jaundice, which can reduce jaundice faster and reduce the risk of bilirubin encephalopathy. In the case of pathological jaundice caused by biliary anomalies, such as biliary atresia, blue light irradiation is not very useful, and prompt surgical treatment is required in this case. Physiologic jaundice and breast milk jaundice do not require blue light treatment; the former can be given more sunlight, while the latter also requires timely discontinuation of breastfeeding.