The purpose of this study was to evaluate effects of bone regeneration by the external sources of human bone substitutes which were developed for the transplantation. There are many different forms of bone based substitute materials. This study is focused on transplantable bone products developed by HansBiomed Inc. and some selected products, namely, human cortical bone powder, demineralized bone matrix(DBM), and bovine bone powders. SureOss and SureFuse are freeze-dried form of human cortical bone powder and DBM combined products, available from HansBiomed Corp, Korea, and Bio-Oss is the granule form of bovine bone powder by Geistlich- Pharma, Switzerland. The 4-mm critical size skull defects in athymic rats were prepared, and the defects were filled with the materials to be tested. The animals were sacrificed at 12 weeks. New bone formation was assessed by optical, radiographic and histological analyses. In our results, photographical density showed that SureOss-graft model induced the best bone formation occurring from defect edges. In summary, our findings indicate that human cortical bone powder enhances bone formation in rat model and the new products based human cortical bone powder may be a good bone substitute material for allografts.