Eleven sternal chondrosarcomas were reviewed with radiologic emphasis on the CT findings. Typical clinical presentation was a large painless anterior chest wall mass in an elderly individual. In six cases the chest radiograph strongly suggested an underlying cartilaginous neoplasm owing to the appearance of typical mineralized cartilage matrix, i.e., a pattern of stippled, flocculent, or curvilinear (“rings and arcs”) calcifications. Calcifications were detected on CT in all 11 patients. Excepting the three smallest lesions, averaging 4 cm in diameter, on CT the tumors exhibited a scalloped or lobulated contour, also typical for cartilaginous neoplasms. Six tumors were centered in the sternal body, four in the xyphoid process, and one in the manubrium. In addition, CT was especially important in localizing the lesion when the tumor was either small in size or centered in the xyphoid process (where all four chondrosarcomas grew in an inferior direction). Because of its ability to detect subtle matrix mineralization and delineate the extent and probable origin of the tumor, CT strongly favored the preoperative diagnosis of sternal chondrosarcoma and was also helpful in surgical management.