Application of computer tomography (CT) and other modern methods of topic diagnosis have permitted to reveal "silent" adrenal tumors more frequently. To conduct a timely and radical treatment it is necessary to estimate the stage of malignancy and hormonal activity of these tumors. There were analyzed the results of treatment of 90 patients with malignant hormonally--inactive adrenal tumor. The size of the tumor, as well as data of CT and magnetic resonance tomography constitutes the criterions, determining the malignant origin of the tumor and indications for operation performance. Application of fine-needle aspiration puncture biopsy is indicated for diagnosis of presumably metastatic adrenal affection. The open extraperitoneal lumbotomic adrenalectomy is the only radical method of treatment of adrenal malignant tumor. For diagnosis of presumably malignant epinephric affection application of endoscopic technique is contraindicated.