:Bone morphogenetic proteins (BMPs) belong to the family of transforming growth factors-β (TGF-β) and play an essential role in the cellular proliferation and differentiation. Trails that used immunohistochemistry have shown that Ki67 is existed in all normal cells which is in proliferating phase and absent in differentiated cells in resting phase. Aim : to investigate the effects of rhBMP-2 on the proliferative activity of rabbits bone tissue using Ki67 staining.