Fine-needle aspiration (FNA) biopsy has become the procedure of choice for initial diagnosis of adrenal masses. However, there have been relatively few reports discussing the FNA cytologic features of adrenal cortical carcinoma. Recently, we experienced a case of FNA cytology of bilateral adrenal cortical carcinoma in a 61-year old man. The smear revealed loosely cohesive pleomorphic tumor cells with hemorrhagic and necrotic background. The tumor cells showed oval to spindle hyperchromatic nuclei and prominent nucleoli with frequent mitotic figures. The cytoplasm of tumor cells was relatively abundant and sometimes vacuolated. These cytologic findings were interpreted as an ad renal cortical carcinoma, undifferentiated pattern.