Thymic carcinoid or neuroendocrine tumor of thymus is a very rare disease and has poor prognosis due to frequent recurrence and distant metastasis. A 43-year-old man was refered to our hospital because of Rt. chest pain and tightness. Chest X-ray revealed $7{ imes}8$cm sized mass on Rt. anterior mediastinum. Surgical excision was performed and light microscopic, immunohistochemical and electron microscopic findings were confirmed as atypical thymic carcinoid tumor with thymic cyst. The patient has been followed up without recurrence or distant metastasis postoperatively for 3 months to now. We report a case of atypical thymic carcinoid with thymic cysts.