Objective To investigate CT in combination with MRI in diagnosing and differential diagnosing chondrosarcoma.Methods CT and MRI findings pathologically in 19 cases of chondrosarcoma proved were analyzed retrospectively.Results On CT,the tumors appeared as bony destruction in 15 cases,soft tissue masses in 14 cases,and with multiple calcifications in different shape.Postcontrast CT scan demonstrated peripheral and septal enhancement in 2 cases,and inhomogeneous enhancement in 3 cases.On MRI,the chondrosarcomas were hypointense or isointense on T1WI,heterogeneous hyperintense on T2WI.Postcontrast MRI demonstrated peripheral and septal enhancement with wreath-or honeycomb-like appearance in 9 cases,heterogeneous enhancement in 2 cases,obvious enhancement in 2 cases.On fat-suppression T2WI,the boundary and size of lesions were demonstrated clearly.The phylloid and cauliflower-like shape of tumors were displayed better on sagital and coronal position.Conclusion CT and MRI are both important in diagnosis and differetial diagnosis of chondrosarcoma,the combination of the two methods may improve the diagnosing accuracy of this tumor and minimize misdiagnosis.