This study investigated the relationship between emotion regulation deficits and posttraumatic symptomatology (PTS), internalizing, and externalizing behavior problems in a sample of 46 maltreated children recruited through the Healthy Coping Program (Muller & Di Paolo, 2008), prior to treatment. Caregivers rated their child using the Emotion Regulation Checklist, the Trauma Symptom Checklist for Young Children, and the Child Behavior Checklist. Problems in emotion regulation were conceptualized on two dimensions: poor emotion understanding and emotion dysregulation. Analyses revealed that both dimensions were significantly related to overall PTS and internalizing behavior problems; however, only emotion dysregulation was significantly related to externalizing problems.