A case of virilizing adrenocortical carcinoma is reported. A 35-year-old woman was referred to our clinic because of left adrenal mass detected incidentally by ultrasonography. At the time of admission, facial acne, systemic hirsutism, hypertrophied clitoris and amenorrhea for two months were observed. Serum testosterone showed obviously high level and urinary 17-KS and 17-OHCS showed slightly high level. A computed tomography revealed a heterogeneous mass with calcification in the left adrenal region. Selective angiography revealed hypervascularity. Under the preoperative diagnosis of virilizing left adrenal tumor, left adrenalectomy was performed. The tumor measured 8 x 6 x 7 cm, and weighed 194 g. A diagnosis of adrenocortical carcinoma was made by pathological examination. Virilizing adrenocortical carcinoma is very rare in adults. We reviewed and discussed 10 cases of virilizing adrenocortical carcinoma in adults, including our case, in the Japanese literature.