Hemoglobin-based blood substitute is widely studied. As the starting materials, hemoglobin (Hb) is mainly supplied from outdated human blood and animal sources. But there are many disadvantages. As the alternative source, human placenta hemoglobin (PHb) has its own advantages. We take the lead in being occupied in the research of blood substitutes based on the placenta blood. Purified PHb readily undergoes dissociation to form two dimers that are easily filtered by the kidneys and have high 02 affinity (low P50), failing to transport 02 to tissues. As a first step, to enhance PHb stability and P50, we first adopted DBBF to modify deoxyPHb leading to DBBF-alpha PHb. According to detection, we knew that the PHb stability was improved, 02 affinity of the PHb solution was reduced, DBBF-alpha PHb had the appropriate capacity of oxygen-carrying and oxygen-unloading, and DBBF-alpha PHb kept the biological activity well. On the whole DBBF-alpha PHb could be considered as a first step toward the synthesis of a potential blood substitute.