Objective To discuss the definition of complicated giant cell tumor of the bone and retrospectively analyze the treatment protocols and their therapeutic results so as to provide a clinical basis for reducing the postoperative recurrence of this kind of tumor. Methods From April 2001 to April 2005, 22patients (11 males and 11 females, aged 15-66 years) with complicated giant cell tumor of the bone were treated by the marginal or wide excision. The tumor was located in the distal femur in 10 patients, the proximal tibia in 5, theproximal femur in 2, the proximal humerus in 2, the hip bone in 2, and the distal radius in 1. The Campanicci′s grading system was used and the patients were grouped as follows: Grade Ⅱ in 4 patients, and Grade Ⅲ in 18. The functional results of the patients were assessed by the clinical examination. The reconstruction methods were used in the forms of osteoarticular allografting (14 patients) and total arthroplasty (8 patients). Results The analysis on the follow-up (6-48 months, averaged 23 months) of the 22 patients revealedthat the complicated factors were as follows: the tumor breaking through the cortex with an extraosseous mass; the tumor having pathologic fracture; the tumor representing more biologically-aggressive lesions; and the tumor having one or more local recurrences. Two patients (9%) had a local recurrence respectively 8 and 11 months after operation, but improved respectively by limb amputation and radiotherapy. Total arthroplasty achieved a better articular function than osteoarticular allografting. All the patients with osteoarticular allografts showed various degrees of the bone union of the allograft with the host bone. Conclusion The marginal or wide excision of this kind of complicated giant cell tumor of the bone combined withosteoarticular allograft or total arthroplasty can reduce the local recurrence of the tumor and achieve a certain degree of the articular motion function.