Neoadjuvant chemotherapy combined with surgery is a major breakthrough in the history of osteosarcoma treatment and offers hope for the survival of patients with osteosarcoma. Neoadjuvant chemotherapy was applied with high doses of methotrexate (8 g/m2´1 day), epoetin (60 mg/m2´1 day), isocyclophosphamide saddle (2 g/m2´5 days), and cisplatin (60 mg/m2´1 day). After the diagnosis was confirmed by pathological examination, 3 cycles of chemotherapy were administered, and a reasonable limb-preserving method was selected for surgical treatment according to the Enneking stage and site of the lesion. The expanded resected tumor specimens were subjected to tumor necrosis rate (HUVOS method) analysis, and the postoperative chemotherapy regimen was determined by combining the patient’s symptoms, signs, imaging examinations and tumor necrosis rate analysis results after preoperative chemotherapy with 6 cycles of chemotherapy.