Objective To study the value and limitation in localized,gualified and diffenential diagnosis of primary malignant tumor of chest wall by CT.Methods CT featares of primary malignant tumor in chest wall comfired by pathology in 7 cases were analysed combined with pataologic findings.Results Of 7 patients,5 cases were originated from soft tissue of the chest wall ( 2 liposarcoma,2 fibrosarcoma ,one rhadomyosarcoma).And 1 case was osteosarcoma of sternum and one case was costal chondrosarcoma.CT imaging:the tumor invaded extra-tissue of chest wall in 3 patients and intra tassue of chest wall in 2 patients,both intra and extra tissue of chest wall in 2 patients.Chest bone hed destruction in 5 patients there were metastases of lung in 4 patients.Conclusion CT scan is of some value in evaluating the location,extent and lung invasion of malignant tumor of chest wall.