Eating disorders (EDs) and posttraumatic stress disorder (PTSD) are frequently comorbid psychological conditions in persons who have experienced traumatic life events. This study investigates a gendered analysis of the co-occurrence of symptoms of ED, PTSD, and dissociation using perceived causal relations (PCR) scaling in a convenience sample recruited online (n = 519; 221 male, 298 female) as well as in women seeking inpatient treatment for EDs (n = 21). Within the Internet sample, trauma exposure and PTSD symptoms were associated with EDs-related behaviors in both women and men, although the association between dissociative experiences and EDs-related behaviors was particularly strong in men. Moreover, dissociative experiences were found to mediate the association between trauma history and EDs symptoms in both women and men. PCR scaling suggested that participants perceive their PTSD symptoms and ED-related behaviors to be causally related, with particularly strong ratings evinced by the clinical sample. The implications of these results for understanding the comorbidity and effective treatment of persons with EDs and trauma-related disorders are discussed.