To provide a bone graft substitute having an appropriate absorption period in a living body and high osteoconductivity, the bone graft substitute contains a carbonate apatite and an osteoinductive factor, the osteoinductive factor is preferably at least one kind selected from a group including BMP (a bone morphogenetic protein), GDF (a growth differentiation factor), TGF-.beta. (a transformation growth factor), FGF (a fibroblast growth factor), IGF (an insulin-like growth factor), PDGF (a platelet-derived growth factor), BDNF (a brain-derived nerve growth factor), and NGF (a nerve growth factor), and the bone graft substitute has open pores, preferably having a diameter of 50 to 1000 .mu.m and/or a diameter of 0.001 to 5 .mu.m, with porosity of 20 to 80%.