Psychological factors like traumatic life events seem to affect the etiopathogenesis and the exacerbation of fibromyalgia (FM), a chronic widespread musculoskeletal pain syndrome. This Study investigated the prevalence of traumatic events, with a particular attention to the whole life span, and both psychoform and somatoform dissociation in patients with FM, compared with healthy controls (HC). In addition, the possible effects of traumatic events and dissociative experiences on FM symptoms have been analyzed. Traumatic experiences, dissociative symptoms, and psychological distress were assessed in 99 consecutive patients with FM and 107 healthy women. Student t-tests for two independent samples were used to determine differences between the FM and HC groups. A hierarchical multiple regression analysis was used to explore the possible contribution of trauma and dissociation to FM symptoms. Results revealed that the levels of both somatoform and psychoform dissociation were higher among patients with FM than HC ( < .001). Moreover, patients with FM experienced significantly more negative life events than HC ( < .001). Finally, the data suggested that the severity of FM disabilities was significantly predicted by the presence of depressive symptoms, somatoform dissociation, cumulative trauma, and educational level. The final Model explained 40% of the variance. Results suggest that the construct of somatoform dissociation could serve as a useful framework to improve our understanding of FM symptoms, and stressed the importance of evaluating the effects of multiple traumas in cumulative form because this has substantial implications for the evaluation and treatment of patients. (PsycInfo Database Record (c) 2021 APA, all rights reserved).