Emotional process at times goes awry. For instance, depersonalization disorder includes emotional detachment, which is evoked sometimes by stressful events, just like a common symptom of acute stress disorder. Similarly, psychopathy is characterized by weak emotional responses. However, although they appear to have something in common, these phenomena are not completely the same, and each has some different function for or influence on behavior. We investigated the differences between emotional detachment in depersonalization and weakened emotion in psychopathy, using Emotional Processing Scale (EPS). Path analysis revealed that emotional malfunctions in depersonalization could be separated into dissociation, which was common with primary psychopathy, and suppression, uncontrollability, and confusion, which were common with secondary psychopathy.