This study examines the association between expectant parents’ psychological distress and children’s development at 36 months old. This is a prospective population study based on the Norwegian Mother and Child Cohort Study, N = 31,663. Logistic regression models were used to assess whether high scores (cutoff ≥2.00) on the symptom checklist-5 in parents predicted higher levels (cutoff ≥90 percentile) of developmental problems in their children. The risk of emotional and behavioral problems were significantly increased in children when both parents were affected by psychological distress during pregnancy, fully adjusted OR 2.35 (95 % CI 1.36, 4.07) and OR 2.65 (96 % CI 1.564.48), respectively. The risk was higher when mothers reported high level of psychological distress than when only the fathers did, but the risk of emotional difficulties in children was highest when both parents presented high levels of psychological distress, indicating an additive effect of parental psychological distress.