The frequency of eating disorders has been increased over the course of last 50 years. Its history reveals that different forms of eating disorders have actually been existed for a long period of time but the most recognized eating disorders like Anorexia Nervosa and Bulimia Nervosa have only recently been included to the official classification systems. It is being argued that biological genetic load and hypothalamic neuromediator factors are the main causes for the etiology of eating disorders, which may cause appearance of several physical symptoms, have a poor prognosis, have a high risk of recurrence, and have a high rate of fatality among psychiatric disorders. Among psychological factors, the emphasis is on family structure and the patient-family relations, and it's being claimed that the form of the relation that the patient has with his/ her parents is effective on eating disorders. It's expressed that the families of patients with eating disorders are less emphatic, less supportive and have higher expectations. Furthermore, findings reveal that more cases of familial problems and fights, depression, anxiety, alcoholism and any kind of eating disorder are being encountered within the families of patients with eating disorders. In this study the literature on the relationship between eating disorder and family structure has been reviewed.