ObjectiveTo investigate the clinical outcome of application of joint prosthesis in limb salvage treatment of mildmalignant tumor at the articular ends of femurs, with severe osteolysis. Methods The treatment of 15 cases of mildmalignant tumor at the articular ends of femurs with severe bone destruction, from 1978 to 1999, was reviewed. There were 10 cases of giant-cell bone tumor and 5 cases of chondrosarcoma, among which there were 5 cases at the stage ofⅠA, 9 cases at ⅠB, and 1 case at ⅡA, with 4 cases at the proximal end and 11cases at the distal end. The tumor was totally removed, with a massive bone defect left at the foci, and then the prosthesis replacement was performed to reconstruct the articular joint. All of the 15 patients were followed up for 9 monthsto 20 years, 4 years and 3 months on average, before clinical evaluation. Results All of the wound healed well, with primary healing. Local relapse occurred in one case and the patient died of lung metastasis; the amputation of the replaced knee joint was performed in one case due to severe infection after trauma; radiograph showed there was slight sunk of the prosthesis in 2 cases after replacement. The other 11 cases recovered well with satisfactory function. Conclusion The limb salvage treatment of mildmalignant tumor at the articular ends of femurswould be available, especially for those with massive bone destruction, when the tumor is removed by whole and rationally marginal resection, followed by properlyutilization of prosthesis and general post-operative exercise.