Ten patients with adrenal cortical carcinoma were treated from 1966 to 1986. There were 7 males and 3 females. The typical clinical manifestations, marked increase of 17-ketosteroid, 17-hydroxycorticoids and DHA, and negative dexamethasone suppression test were essential for the diagnosis. Of the ten patients, eight had secretive function and their 17-ketosteroid and 17-hydroxycorticoids varied from 36.8-93 mg% and 32.5-150 mg%, respectively. DHA was measured in 5 cases with the result of 6.95-44mg%. Those without secretive functions or obvious endocrine disturbances were usually misdiagnosed as kidney tumor, splenomagaly, liver tumor or pancreatic mass. Wood had summarized that nonsecretive ACC patients commonly had fever, pain, exhaustion syndrome (emaciation, fatigue, perspiration, anorexia), mass and distant metastasis. Adrenal scan, IVU, abdominal aortic arteriography, retroperitoneal pneumography and CT were helpful in localization. The differential diagnosis between ACC and adenoma by pathology was difficult. It is generally agreed that if the mass is larger than 100 grams, capsulated, having blood or lymphatic vessel invasion, hemorrhage, necrosis and calcification or even distant metastasis, malignant tumor should be considered. Surgical removal of the tumor is the only effective treatment. For advanced or recurrent lesions, selective adrenal artery thrombosis could be used. One of the ten patients was thus treated by this facilitated subsequent surgery. Postoperative chemotherapy, such as O.P-DDD, might be used in some cases.