Abstract:  To investigate the computerized tomography ( CT ) appearances of thymic carcinoid. Methods: The clinical data and CT appearances of 8 pathologically confirmed thymic carcinoid cases were retrospectively analyzed, together with a review of literature. Results: Thymic carcinoids have not been characterized in clinical findings. Carcinoid syndrome was found in one case. On plain CT, tumors were usually of isodense slightly hypodense compared to muscle tissue. The density of the tumors was homogeneous ( 2/8 ) or heterogeneous ( 6/8 ), and showed necrosis or cystic degeneration ( 6/8 ). After injection of the contrast medium, the tumors showed marked homogeneous enhancement ( 2/8 ), slight or moderate enhancement ( 5/8 ), and apparent heterogeneous enhancement ( 1/8 ). Moreover, linear enhancement of the blood vessels was observed in the tumors of two cases. The tumor margins were usually ill-defined, extending into the vessel spaces, and often invading or compressing the vessels ( 5/8 ) or pericardium ( 1/8 ). Lymph node metastases were common in thymic carcinoids ( 4/8 ), and distant metastases were frequently observed in the pleurae, lung, bone, and liver ( 4/8 ). Conclusion: Thymic carcinoid is a rare tumor in the anterior mediastinum. The CT findings reveal definite characteristics. Tumor density is heterogeneous with necrosis or cystic degeneration and slightly or moderately enhanced after bolus injection of contrast medium. The CT image can indicate the diagnosis of thymic carcinoid and is helpful for surgical planning. However, the final diagnosis still depends on histopathology.