Simultaneous occurrence of two neoplasms of different cell origin in one thyroid is a known but rare event. Several cases of mixed thyroid carcinoma have been reported and most of the them have been associated with medullary carcinoma. But coexistance of papillary carcinoma and follicular carcinoma in the same lobe of the thyroid was rare. We report a case of mixed papillary and follicualr carcinoma of the thyroid. A 63 year-old man complained of anterior neck mass. Fine needle aspiration cytology revealed suspicious papillary carcinoma and thyroidectomy performed later showed mixed thyroid-follicular carcinoma of the same thyroid lobe.