The author reviewed 12 cases of giant cell tumors which sere treated between January 1980 to May 1986. The results of various methods of treatment applied were compared & literatures surveyed. The following results were obtained. 1) The highest incidence occurred in twenties and there was no difference in sex distribution. 2) The most frequent site was the intertrochanteric area of the femur & 4 cases (33%) occurred around the knee joint. 3) As the primary treatment, curettage & bone graft was performed in 5 cases, curettage & cementation in 2 cases, resection in 2 cases, local excision in 1 cases & radiotherapy in 1 case. 4) 3 cases recurred and their primary treatment was curettage & bone graft. 5) As the secondary treatment, curettage & bone graft was performed in 1 case & curettage & cementation in 2 cases.