Giant cell tumor of bone is a low-grade malignant tumor, and the recurrence rate is extremely high simply by scraping the tumor, and the clinical treatment effect is relatively poor, especially prone to local recurrence and tumor grade rise after surgery, and lung metastasis occurs in serious cases, which is life-threatening. Nowadays, amputation surgery is too great for functional damage and unacceptable to patients. The treatment of giant cell tumor of bone is generally based on internal fixation of bone graft by scraping the lesion or bone cement filling, the main drawback of both is the high recurrence rate after surgery. For giant cell tumors that have invaded most of the bone ends, the joint surface has collapsed, or the pathology has been changed by fibrosarcoma, resection of the tumor segment and tumor-based prosthesis replacement can be used. Tumor-based prosthesis is a custom-made prosthesis that matches the size of the tumor and the extent of surgical resection, and is currently the most advanced reconstruction method for limb-preserving treatment of bone tumors. It is usually made of alloy materials and is designed specifically for patients with specific bone tumors. Its main advantages include: no rejection, early restoration of skeletal stability and limb movement and significantly reduced complication rate; more complete treatment of bone giant cell tumor and significantly improved patient survival index. The disadvantages are complex surgery, high technical requirements and high costs. In recent years, the Department of Bone Oncology has adopted customized tumor-based prosthesis replacement to do limb preservation surgery and achieved good results. Since 2010, more than 60 patients have been successfully operated with this technology, which has relieved the pain, preserved the limbs and improved the quality of life.