The purpose of this study is to compare the osteogenic activity of pBMP combined with the following, freeze-dried allogeneic bone, surface demineralized allogeneic bone, and demineralized allogenic bone powder in rats. So, authors made partial purification of the pBMP. Using rat calvaria, an 8mm size in diameter boney defect was grafted using pBMP-ibm in the experimental group A as the control group, freezed dried allogeneic bone graft plus pBMP-ibm in the experimental group B, surface demineralized allogeneic bone graft plus pBMP-ibm in the experimental group C, and demineralized allogeneic bone powder plus pBMP-ibm in the experimental group D, respectively. The rats were sacrificed at the week of 1st, 2nd, 4th, 8th after implantation and examined grossly, biochemically, biomechanically, microscopically. The results were as follows 1. Ares of Implanted defect acquired osseous union at post op 4th week. 2. According to the result of hardness test, the experimental group B was most rigid than any other experimental groups at post op. 4th week. And the experimental group B, C and D were more rigid than the experimental group A at post op. 8th week. 3. As time goes on, calcium content of implanted area has increased gradually in all experimental groups except the experimental group B. 4. In the early stage of grafting, the new cartilage formation & new bone formation were more active in the experimental group B, C and D than in the experimental group A, but in the late stage of grafting, there was no significant difference in the new bone formation among the experimental groups. 5. New cartilage and new bone formation occurred as follow, first in the experimental group D, then the experimental group C, the experimental group B, the experimental group A, respectively.