The best time to screen the fundus of the eye in preterm babies is usually 4 to 6 weeks after birth, and it is very necessary for preterm babies to have fundus screening. Fundus screening can check the morphology and color of the optic nerve and optic papilla, the vascular morphology of the retina, the ratio of arteriovenous and whether the macula is normal or not. Preterm infants, due to their earlier birth, have immature retinal vascular development, which will easily affect their vision in the future, and should be screened in time, usually 4~6 weeks after birth, to avoid retinopathy, which will affect their vision. Due to the imperfect development of the body system, preterm infants should pay attention to care, preferred breastfeeding, or the use of preterm infant formula, pay attention to warmth, pay attention to the way of newborn feeding, to avoid choking, stay away from infected people.