Papillary carcinoma arising in a thyroglossal duct cyst is a rare tumor. We report the case of 64-year-old man treated for thyroglossal duct cyst. Preoperatively, the thyroid gland was normal on physical examination and imaging studies. The Sistrunk procedure was done. The histopathological examination revealed thyroid papillary carcinoma. Postoperatively thyroid hormon was given to suppress serum TSH levels and the patient was followed at regular intervals. During a 5-year follow-up period, no recurrence of the disease occured.