We treated two patients with Schmidt's syndrome who showed some differences in the endocrinological findings in adrenal steroidogenesis. However, there had been no reports describing in detail which zone(s) is most usually destroyed in the adrenals in Schmidt's syndrome of which the pathogenesis is thought to be intimately related to immunological disturbances. Case 1 is a 63-year-old female, presenting a complete deficiency of almost all adrenal steroids. Case 2 is a 53-year-old female, showing a partial deficiency of adrenal steroids, and examination of various plasma adrenal steroids suggests that impairment of the zona fasciculata may be mainly confined to the adrenal cortex. The results of aspiration biopsy cytology of the thyroid demonstrated the presence of chronic thyroiditis in each case. Case 2 also presented empty sella detected by MRI of the pituitary gland. It is therefore suggested that zona fasciculata cells may be first destroyed and the impairment seems to spread to all zones in the adrenals in Schmidt's syndrome. Moreover, some patients with Schmidt's syndrome may have empty sella.