Osteoinducin is a kind of new biomaterial, which contains bone morphogenic protein (BMP). Its role of inducing osteosis has been confirmed by laboratory study. Since 1992, osteoinducin was applied to treat tumorous defects of bone for 7 cases. After eradication of the lesion of tumor, stickor granulelike osteoinducin was filled in the defects. In 8 weeks, the bone defects had the sign of osteosis on roentgenogram. No rejection reaction and local inflammation were found. The property, operation procedure and indication were introduced. Compared with other artificial bones, the osteoinducin showed faster osteosis, better histoco mpatibility and more convenient usage. It was a good material for bone graft.