PURPOSE: The aim of the study was to determine the risk factors for the development of cystic periventricular leukomalacia (PVL) in preterm infants and the neurologic outcomes according to its extent and site of cystic PVL. METHODS: Forty-four preterm infants whose a gestational age ranging from 25 to 34 weeks with cystic PVL documented by cranial ultrasonography and other forty-four preterm infants without brain abnormality were enrolled in this study. We determined perinatal and neonatal risk factors for the development of cystic PVL in these infants. The forty-four preterm infants with cystic PVL were divided into two groups according to extent and site of cystic change by cranial ultrasonographic findings. Infants were included in localized group when the extent of cystic change was localized in one lobe and in diffuse group when the extents of cystic change was located in more than two lobes. We compared the differences of the perinatal and neonatal risk factors and neurologic outcomes according to its extent and site of cystic PVL between the two groups. RESULT: Neonatal sepsis was the only significant risk factor for the development of cystic PVL (P<0.05). There were no significant differences of perinatal and neonatal risk factors between infants with localized cystic PVL and diffuse cystic PVL. Diffuse cystic PVL was diagnosed earlier than localized cystic PVL (P<0.05). Cerebral palsy and convulsion were more common in infants with diffuse cystic PVL than localized cystic PVL (P<0.05), and infant with the involvement of occipital lobe showed high risk of cerebral palsy. CONCLUSION: With the more diffuse extents of cystic PVL and when the cystic change in occipital lobe, the risk of neurologic problem was high. And diffuse cystic PVL was diagnosed earlier than localized cystic PVL.