PURPOSE: To identify the risk factors for poor neurodevelopmental outcomes in high-risk neonates. METHODS: We studied 94 infants admitted to the neonatal intensive care unit at the Sanggye Paik Hospital between January 2002 and November 2005 and evaluated the follow-up data. The following events were considered as risk factors: < or =32 weeks of gestation, very low birth weight, Apgar scores of less than 5, neonatal resuscitation, neonatal seizure, congenital infection, and abnormalities in cranial ultrasound or magnetic resonance imaging (MRI). The infants who had any one of these risk factors were included. They were evaluated at their mean corrected age of 13.84+/-8.03 months. Mental and Psychomotor Developmental Indices (MDI, PDI) were determined by a clinical psychologist using the Bayley Scales of Infant Development II. RESULTS: The mean MDI and PDI of all the patients were 96.28+/-26.70 and 94.00+/-22.80, respectively. Abnormalities on cranial ultrasound or MRI were significant predictors of both low MDI (P<0.05) and low PDI (P<0.001). These abnormalities showed a stronger association with low PDI than with low MDI. The infants with periventricular leukomalacia had the lowest MDI and PDI (70.10+/-28.68 and 69.70+/-24.91, respectively). Apgar score at 1 minute and very low birth weight were also significant predictors for low PDI (P<0.05, P<0.05, respectively). CONCLUSION: Image findings with cranial ultrasound or MRI were the strongest predictors of neurodevelopmental outcome. Periventricular leukomalacia was the best predictive factor for mental and psychomotor development.