We analysed the thirty three cases of the free vascularized bone graft performed in the Department of Orthopaedic Surgery, Yonsei University College of Medicine from February 1982 to December 1989 and would like to report the results as follows. 1. There were 27 cases in men and 6 cases in women and the mean age was 27.3 years. 2. We have performed the procedure for the reconstruction of the large bony defects developed after massive trauma in 13 cases, core decompression of the avascular necrosis of the femoral head in 8 cases, tumoral resection in 6 cases, treatment of congenital pseudoarthrosis in 3 cases, and bone infection in 3 cases. 3. The most common recipient site was tibial shaft (18 cases, 54%) and the most common donor site was fibular shaft (23 cases, 69%). 4. The average length of bone defect (or grafted bone) in 23 cases of vascularized fibular graft was 9.8 cm and in 9 cases of vascularized osteocutaneous iliac bone graft, it was 5.8 cm. 5. The follow-up period was ranged from 13 months to 5 years 8 months (mean, 2 years 2 months). 6. All patients were evaluated clinically and roentgenographycally on the basis of fuctional recovery and bony union. Of the 33 cases, 31 cases (93%) showed satisfactory functional recovery with sound bony union. 7. It is highly expected that the vascularized bone graft is a one of the better alternatives for the reconstruction of the large bone defect and prevention of the early state of the avascular necrosis of the femoral head from progession.