The study objective was to measure and compare the presence of childhood trauma and dissociative symptoms in a convenience sample of healthy controls and a probabilistic sample of outpatients with a diagnosis of schizophrenia. Patients reported more childhood trauma and more polytraumatization than the controls, and had a higher average dissociation score. In both cases and controls, the presence of childhood trauma was related to the intensity of the dissociation observed. Childhood trauma, clinical dissociation and schizophrenia are closely related, particularly when the patient has been the victim of more than one type of abuse.