We report 4 fullterm newborns who developed retinopathy similar to oxygen-induced retinopathy after high concentration oxygen therapy for pneumothorax and emphysema. Two of them had a severe condition, showing marked dilatation, winding, and abnormal branching of the retinal vessels, especially veins, and retinal trubidity. Comparison between the 4 patients and controls without such retinopathy suggested that factors such as the oxygen concentration, the duration of oxygen therapy, the gradual reduction method, and the high level and changes in PaO2 were involved in the development of the retinopathy. Even in fullterm infants, treatment should be performed with consideration of the possible occurrence of changes in the eye fundus.