OBJECTIVE: To investigate the value of artificial joint prosthesis in the treatment of bone tumors. METHODS: The follow-up results of 88 cases of bone tumor resection and bone defect reconstruction with artificial joint prosthesis were analyzed, including postoperative efficacy, survival, functional status, complications and management. The tumors included malignant bone tumors, benign bone tumors and tumor-like lesions in 52 cases: Ewing’s sarcoma in 4 cases, osteosarcoma (including pelvic osteosarcoma in 3 cases) in 23 cases, chondrosarcoma in 6 cases, malignant fibrous histiocytoma in 3 cases, metastatic carcinoma in 18 cases, aneurysmal bone cyst in 18 cases, and giant cell tumor of bone. There were 26 cases of hinged artificial knee joint, 9 cases of temporary hemi-knee joint, 12 cases of artificial femoral head, 33 cases of artificial total hip joint, and 8 cases of artificial hemi-shoulder joint. Results: 88 cases of tumor-based artificial joint replacement surgery. There were 36 cases of malignant tumor and 52 cases of benign tumor. There were 26 cases of hinged artificial knee joint replacement, 9 cases of hemi-knee joint, 12 cases of artificial femoral head replacement, 33 cases of artificial total hip joint replacement, and 8 cases of artificial hemi-shoulder joint replacement. The artificial joint prosthesis was customized according to the preoperative X-ray and MR, and the malignant tumor was usually treated with 1~2 courses of chemotherapy before the post-chemotherapy X-ray and MR film were used to measure the customized joint prosthesis. Knee prosthesis is hinged; pediatric malignant tumors of the proximal and distal femur and proximal tibia are replaced with hemi-articular prosthesis. The artificial femoral head was Moor type or bipolar artificial femoral head; the artificial total hip joint was cemented with an extended stem; the artificial hemiacetabular joint was Neer type, and all the above prostheses were fixed with bone cement. The patients’ postoperative joint function recovery was observed at the follow-up. RESULTS: Eighty-eight patients were followed up from 4 months to 9 years, respectively, and all of them entered the outcome analysis. Two cases of chondrosarcoma survived for 5 years without tumor, five cases of osteosarcoma survived well after surgery, three of which were 4, 7, and 8 years; the tumor did not recur, four cases of malignant tumor had died, and one case was 2 years postoperative due to recurrent swelling of the knee joint and limitation of movement. In one case, the thigh was amputated due to chronic infection of the prosthesis. The results of artificial femoral head replacement: 12 cases of malignant, 5 cases died in 1~3 years. 2 cases of chondrosarcoma had survived for 3 years, and now the lung metastasis. The results of artificial total hip replacement: the affected hip had good extension and flexion activities and no pain. The patients with malignant tumor died in 6 months respectively. ④One case of artificial hemi-pelvic component type and two cases of personalized 3D reconstruction, one of which had poor postoperative wound healing and repeated exudation, which healed after re-dilatation and drainage. One case was healed after re-dilatation and drainage. ⑤ Artificial hemi-shoulder joint replacement results: no pain in the shoulder joint at postoperative follow-up, some of them had drooping shoulders, and all activities were limited. 1 case of proximal humeral osteomegaloblastic tumor recurred 2 years after surgery and was surgically revised again. Complications occurred in one case (%), including skin necrosis and local recurrence. The follow-up ranged from 4 months to 7 years, with a mean of 32 months. One case of local recurrence of osteosarcoma was converted to amputation, and one case of osteosarcoma developed pulmonary metastasis. The final limb preservation rate of patients with malignant bone tumors was 92.8%. The rate of excellent functional assessment was 80%. The 5-year tumor-free survival rate was 34.18% (8/23), the 5-year survival rate was 52.12% (12/23), the local recurrence rate was 17.14% (4/23), and the final limb preservation rate was 82.16% in 23 cases of malignant bone tumors. 30 cases of benign bone tumors had a complication rate of 40% (8/20), and the overall limb preservation rate was 85% (17/23). Conclusion: Customized tumor-based artificial joints have good application in limb preservation treatment of bone tumors, but the prosthesis design should be further improved to facilitate soft tissue reconstruction and reduce complications. The selection of surgical indications should be extended to improve the level of patient survival. Malignant tumors should be treated preoperatively with chemotherapy and restaged after chemotherapy, and surgery should follow the tumor-free principle for extensive resection. Reconstruction of soft tissues during surgery is important to improve the function of tumor-based artificial joints.