Although giant cell tumor of bone is a benign bone tumor, it is prone to recurrence after simple curettage because of its aggressive growth characteristics. In recent years, more and more hospitals use osteotomy and artificial prosthesis to treat giant cell tumor of the limbs, which avoids recurrence after surgery, but at the expense of their own joints and expensive treatment costs, and the artificial prosthesis has a certain service life, and most patients still need another surgery to revise and replace the artificial joint. We have successfully treated giant cell tumor of bone using in situ microwave inactivation. The basic idea is to thoroughly inactivate the tumor and its surrounding area with multiple inserted microwave electrodes, followed by scraping the inactivated tumor tissue, filling the tumor cavity with bone cement or bone grafting, and deciding whether to perform internal fixation with a plate depending on the degree of bone destruction. Since the tumor tissue is completely inactivated to avoid postoperative recurrence, the tumor segment is not osteotomized to preserve the joint, and the prosthesis replacement is not needed to save the treatment cost.