The purpose of the present study was to examine the temperament and behavior problems of 32 toddlers born preterm and very low birth weight and 25 toddlers born full-term without medical problems. Mothers completed the Early Childhood Behavior Questionnaire and the Child Behavior Checklist-1.5–5 for assessing toddler`s temperament and behavior problems, respectively. The results showed that, regarding temperament, toddlers born preterm exhibited higher scores on the temperament dimensions Motor Activation, Perceptual Sensitivity, and High Intensity Pleasure, and lower scores on the temperament dimension Cuddliness than toddlers born full-term. In regard to behavior problems, toddlers born preterm showed higher attention problems scores than the comparison group. These findings indicated that children born preterm presented developmental vulnerabilities in temperament dimensions related to behavior problems at toddlerhood. Early intervention programs for preventing psychological problems in at-risk children, especially those born preterm, could focus on children’s temperament dispositions.