Retrospective study on diagnosis and management during the perioperative period of patients with adrenal tumors who underwent adrenalectomy in the Second Department of Surgery Kyoto University, from 1960 to 1983, was carried out. Most of the patients presented with functioning tumors; primary aldosteronism (43 cases), Cushing's syndrome (53 cases), pheochromocytoma (39 cases), and DOC-producing tumor (1 case), whereas, only 3 cases were non-functioning adenoma and cyst. Although recent development of CT has permitted easy and non-invasive diagnosis of adrenal tumors, aldosterone-producing tumors may be overlooked due to their small sizes, because their CT value is identical to that of fatty tissue. Moreover, blood sampling from vena cava at various levels is also necessary in patients with extra-adrenal pheochromocytomas. The preoperative control of blood pressure by alpha- and beta-adrenergic blocking agents was a prerequisite, and the clinical course was uneventful following intraoperative additive use of sodium nitroprusside in patients with pheochromocytoma. Autotransplantation of the adrenal cortex into the rectus muscle was performed in three patients with bilateral pheochromocytoma and two of them could return to work. Non-functioning adrenal tumors have been found increasingly by routine CT study without previous suspicion and the surgical indication of these tumors must be discussed in more detail in the future.