We report a 50-year-old man with mediastinal tumor. The patient received the thoracoscopic resection for mediastinal tumor with the operative time of 1 h and intraoperative blood loss of 10 mL. The final diagnosis after surgical excision was an ectopic papillary thyroid carcinoma. The patient recovered well without surgery-related complications, and was discharged on the 2nd day after the operation. No recurrence was found during the follow-up. We also reviewed relevant literature to explore the clinical features, diagnosis, and treatment of ectopic thyroid carcinoma.