Objective To discuss CT appearance and differential diagnosis of costal cartilage fracture in adult.Methods CT findings of 30 costal cartilage fractures in 20 cases were analyzed.Results On the basis of fractural location and CT appearanes,the fractures were divided three types:14 line-like fracture in 10 cases,9 local focal cleft within the costal cartilage in 6 cases and 7 massed fractures in 4 cases.Conclusion CT is of great value in diagnosing costal cartilage fracture.