Preterm childbirth increases the risk of developmental problems. The aim of the present study was to examine the effects of temperament and attention on the cognition of school-age children who were born preterm, controlling for socioeconomic variables.The sample was composed of 50 six-year-old children who were born preterm with very low birth weight. The children were evaluated using the Wechsler Intelligence Scale for Children (WISC-III) and the Cancellation Attention Test. The mothers were interviewed using the Children's Behavior Questionnaire (CBQ). Statistical multiple linear regression analyses were performed.70% of the children presented average or above-average full intellectual quotient (IQ). In the attention total score, 74% of the children were also within the average range or above. High verbal IQ associated with high maternal schooling explained 73% variability of the full IQ. High attention and maternal schooling, associated with children's temperament with more effortful control, explained 35% variability of the verbal IQ. High attention, associated with high maternal schooling and socioeconomic level, explained 37% variability of the performance IQ. The neonatal clinical variables (gestational age, birth weight, 5th-minute Apgar, and length of stay in neonatal intensive care unit (NICU) and hospital) were not predictors of cognitive outcomes.The majority of the children who were born preterm presented average or above-average cognitive and attentional performances at school age, demonstrating potential resources for learning. Taken together, attention and temperament, associated with maternal schooling and socioeconomic status, were predictors of cognitive outcomes of children born preterm at school age.