Retinopathy of prematurity is a disorder of the development of retinal blood vessels that affects premature infants and is in many countries, including the Republic of Croatia, the most common cause of blindness in childhood. Among the many risk factors associated with the development of the disease, the most important are low gestational age and low birth weight and related factors such as the percentage of oxygen in the inhaled air, sepsis, poor weight gain, erythrocyte transfusions and others. The main goal of this study is to determine the incidence of ROP in preterm infants of gestational age ≤ 32 weeks treated in the period from May 2018 to May 2021 in University Hospital Centre Zagreb, Department of pediatrics, Neonatal intensive care unit, and define the risk factors that contribute to its development. The data that were collected from medical history and then analyzed include factors related to mother, childbirth, and prematurity. The WINROP algorithm and CRIB II score were used to predict vision-threatening retinopathy. The study includes 77 preterm infants born over a three-year period. The results showed that the incidence of all forms of retinopathy of prematurity was 37.66% and of severe form 9.09%. Gender, gestational age, oxygen therapy, bronchopulmonary dysplasia, and length of hospitalization were identified as risk factors. The WINROP algorithm accurately predicted 55.17% of preterm infants who later developed ROP. Higher CRIB II score is associated with more severe forms of the disease. In most cases, retinopathy of prematurity occurs in a mild form that does not require treatment. As a small percentage of the disease is severe and can progress to retinal detachment associated with severe visual impairment, it is important to conduct screening programs to begin treatment in a timely manner and prevent further disease development.