Despite the fact that the assumption of a relationship between conversion disorder and childhood traumatization has a long history, there is little empirical evidence to support this premise. The present study examined this relation and investigated whether hypnotic susceptibility mediates the relation between trauma and conversion symptoms, as suggested by Janet's autohypnosis theory of conversion disorder.A total of 54 patients with conversion disorder and 50 matched comparison patients with an affective disorder were administered the Structured Trauma Interview as well as measures of cognitive (Dissociative Experiences Scale) and somatoform (20-item Somatoform Dissociation Questionnaire) dissociative experiences.Patients with conversion disorder reported a higher incidence of physical/sexual abuse, a larger number of different types of physical abuse, sexual abuse of longer duration, and incestuous experiences more often than comparison patients. In addition, within the group of patients with conversion disorder, parental dysfunction by the mother-not the father-was associated with higher scores on the Dissociative Experiences Scale and the Somatoform Dissociation Questionnaire. Physical abuse was associated with a larger number of conversion symptoms (Structured Clinical Interview for DSM-IV Axis I Disorders). Hypnotic susceptibility proved to partially mediate the relation between physical abuse and conversion symptoms.The present results provide evidence of a relationship between childhood traumatization and conversion disorder.