Myopia is a frequent sequelae of retinopathy of prematurity. The mechanism for myopia development in children born preterm is not well understood. From a group of 33 myopic preterm children we selected those who had regressed retinopathy and myopic values < or = 5 D. Seventeen children met our criteria. Of them, 10 patients could be re-examined. Factors related to myopia development were analyzed and compared to a control group of 12 children born fullterm with emmetropia or low hypermetropia, as well as another group of 10 fullterm children with myopic values < or = 5 D. The age of children ranged from 9 to 14 years in all groups. The mean birth weight in myopic premature children was 1249.3 g. Higher keratometric diopter values were found in myopic premature children than in emmetropic fullterm children (p < 0.05) and myopic fullterm children (p < 0.05). Increased axial length values were observed in myopic fullterm children when compared to myopic premature children (p < 0.05) In children born preterm the corneal refractive power seems to play a major role in myopia development.