Limb salvage operation in primary malignant bone tumors is increasing recently, according to the improvement of diagnostic methods, surgical technique and adjuvant chemotherapy. The purpose of this study is to obtain the interim results of survival rate and the functional grade of the limb in primary malignant bone tumors treated by limb salvage operation. Between 1985 to 1993, 63 primary malignant bone tumors treated by limb salvage operations. Tumor prosthesis arthroplasty was performed in 49 patients, resection arthrodesis in 9 patients, and IM nailing with cement molding in 5 patients. Autoclave autograft was combined in 2 patients. Adjuvant chemotherapy and postoperative radiotherapy were performed in selected patients. The average follow-up period was 50 months(ranged 12 months to 116 months). In the cases of osteosarcoma, estimated survival rate was 61.9% based on Kaplan-Meier survival plot. In the parosteal sarcoma, the survival rate was 87.5% and 80% in chondrosarcoma patients. According to functional grading by Enneking, 66% was excellent, 20% was good, 11% was fair and one patients was poor. Complications occurred in 16 patients:wound infection was developed in 6 patients, local recurrence in 4, peroneal nerve palsy in 2 patients and femoral stem loosening in 2 patients. Fracture in resection arthrodesis and pulmonary metastasis were also occurred. Reoperation was performed in 10 patients at average 31 months after initial operation. Revision tumor persthesis arthroplasty was performed in one patient due to local recurrence and in 2 patients due to femoral stem loosening. Three amputations were done due to recurrence of tumor. IM nailing with cement molding was performed in one patient due to deep infection and repeated arthrodesis was done in a fracture patients. Scheduled custom-made tumor prosthesis arthroplasty was performed within a year in 2 patients treated with IM nailing with cement molding. In conclusion, with the careful preoperative assessment, adjuvant chemotherapy and skillful surgical technique, limb salvage operation would provide the primary malignant bone tumor patients for longer survival and better quality of life.