The aim was to evaluate neuropsychological performance and its pre-, and perinatal predictors in low birth weight (LBW) preschool children. A population-based sample of 137 5-year-old children with birth weights less than 2000 g and without major handicaps was compared with a random sample of 152 normal birth weight term controls. Main assessment tools were all subscales from the Wechsler Preschool and Primary Scale of Intelligence Revised, subscales from the Illinois Test of Psycholinguistic Abilities and tests of manual dexterity and figure copying. The LBW children showed significantly lower mean scores compared to controls on tests of visuo-spatial and visuo-motor abilities, but were comparable to controls in other areas, confounding parental factors were controlled for. 14 of the LBW children, there were signs of maternal chorio-amnionitis. Twelve of these had premature rupture of membranes lasting more than 24 h. These 14 children had a mean performance IQ of 87 (SD 5) compared to 100 (SD 15) for the LBW children without maternal signs of chorio-amnionitis (P = 0.001). Having a small head circumference at birth was a less powerful, but statistically significant predictor of impaired performance.