The first case of papillary carcinoma of thyroglossal duct cyst in Songklanagarind Hospital is reported. The patient was a 60-year-old man who presented with a midline neck mass. Ultrasound and computed tomography of the mass demonstrated a thyroglossal duct cyst. The patient underwent a Sistrunk operation and the pathological report revealed papillary carcinoma arising from a thyroglossal duct cyst. Postoperatively the patient was placed on thyroid hormone suppression treatment. Currently, the patient is on regular follow-up and doing well without recurrence 6 months after operation.