The purpose of this study was to identify infant and maternal characteristics that predict psychological distress among mothers of preterm infants admitted to the neonatal intensive care unit (NICU). Infant characteristics included birth weight, gestational age, and ventilatory support, and maternal characteristics included age, parity, and socioeconomic status. Mothers (n = 142) completed questionnaires including a demographic form, the Parental Stressor Scale, and the Symptom Checklist 90-R. In hierarchical regression analyses, maternal NICU-specific distress was more strongly predicted by infant characteristics [F(3,135) = 6.80, p < .05] with maternal variables covaried. Maternal general psychological distress was more strongly predicted by maternal characteristics [F(3,135) = 6.05, p < .05]) with infant variables covaried. Twenty-eight percent of mothers reported clinically significant psychological distress compared with 10% in a normative population. Psychological distress among mothers of preterm infants appears to be common and deserves clinical consideration. The use of standardized questionnaires as part of the assessment process may improve case identification and psychosocial service delivery in the NICU.