Abstract: Objective To evaluate diagnostic values of spiral CT-3D and MPR in the benign lesions of the thoracic inlet. Materials and methods: Retrospectively analysis CT findings of 51 cases benign lesions proved pathologically or DSA or clinic at the thoracic inlet. Results: 51 cases benign lesions at the thoracic inlet Include the trachea source lesion 8 cases,and apical lung hernia 3 cases and apical paraseptal blebs 2 cases and benign masses of thyroid 21 cases and esophagus diverticula 3 cases and lymph nodes tuberculosis 5 cases and vascular lesions 9 cases and neurolemmoma 1 cases. conclusion: Spiral CT-3D and MPR is important supplement means in the diagnosis and differential diagnosis of the benign lesions in the thoracic inlet.