Dysfunctional parenting styles are risk factors for eating disorders (EDs). In this observational study, we examined 57 women with ED, a psychiatric control group (n = 26), and healthy participants (n = 60). Several instruments were administered: Defense Style Questionnaire (DSQ-40) to examine the type of defense mechanism used, Parental Bonding Instrument (PBI) to investigate the perception of the relationship with parents, Eating Disorder Examination Questionnaire and Eating Disorder Inventory-3 to assess the severity of the ED, and Body Shape Questionnaire to investigate the perception of their body shape. In patients with anorexia and bulimia, neurotic factor (p = 0.007) and immature factor (p = 0.002) are associated with perception of relationship with their own parents. In the PBI, maternal care was associated with higher scores in the DSQ-40 in the immature factor (p = 0.012), whereas paternal overprotection was associated with lower scores in the DSQ-40 in the mature factor (p = 0.016). Patients with anorexia and bulimia overutilize more neurotic and primitive defense mechanisms compared with nonclinical subjects, and this use is associated with greater severity of eating symptomatology. This can be related to diversified ego forces, can inform about the nature and severity of disease, and can characterize prognostic and psychotherapeutic value.