A 71-year-old man was admitted to our hospital because of the detection of an anterior mediastinal tumor. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed abnormal accumulations in the tumor and the hilar and the supra-clavicular lymph nodes. Preoperatively, percutaneous needle biopsy of the tumor revealed thymic carcinoid. Tumor resection and thymectomy with mediastinal and supra-clavicular lymph nodes dissection were performed because of suspecting metastasis to the lymph nodes from FDG-PET. Postoperative pathological diagnosis revealed atypical carcinoid and metastases to the mediastinal and supra-clavicular lymph nodes. In our case, FDG-PET was useful in detecting the thymic carcinoid and lymph node metastasis. It is desirable to perform clinical research by many facilities for the assessment of FDG-PET as a diagnostic tool and postoperative chemo-radiation therapy for thymic carcinoid.