In certain low-grade malignant tumors such as chondrosarcoma and giant cell tumor, radical treatments may provide a good chance for cure. And large bony defect after the radical treatment can be filled with the massive bone graft. Recent advances in clinical microsurgery have made free tissue transfer a clinical reality, and Taylor in 1975, first reported the technique of free vascularized fibula graft for the reconstruction of large tibial defects with excellent clinical results. >We tried wide excision and free vascularized bone graft in 6 patients with malignant or aggressive bone tumor from April 1981 to November 1985 and followed up for more one year. Mean follow up of free vascularized bone graft is 26.4 months and that of devascularized bone graft is 22.6 months. The results of the free vascularized bone graft were compared with 10 patients who were treated with the wide excision and the devascularized bone graft. In this analysis, free vascularized bone graft is superior to devascularized bone graft in bony union, complications and functional results.