Sheehan's syndrome frequently causes hypopituitarism either immediately or after a delay of several years, depending on the degrees of postpartum ischemic pituitary necrosis. A 55 year-old woman whose last child was born 27 yr ago with massive hemorrhage was diagnosed as postpartum hypopituitarism. She had deficiency of growth hormone, prolactin, gonadotropins and thyrotropin. However, she interestingly had apparent hypercortisolism without suppression response to the dexamethasone tests. We found an adrenal mass with distant metastases to the liver and lung while investigating the origin of the hypercortisolism. Hyperandrogenism and very high levels of 17α, hydroxyprogesterone were present. Accordingly, the patient was diagnosed as hypopituitarism due to Sheehan's syndrome accompanied by Cushing's syndrome as a result of an adrenocortical carcinoma.