Conventional bone repair materials often treat blood as an obstacle through physical isolation or passive hemostasis, overlooking its physiological role in the regenerative cascade. Here, we propose a "Blood-Transforming Coating" concept and engineer a functionalized microsphere system (GM/TCP@PEG). The NHS ester-coated microspheres rapidly crosslink with amino-rich blood components to form a robust hydrogel while covalently anchoring to tissue surfaces, transforming blood into a synergistic component that enhances material function. Structural characterization confirmed the core-shell architecture. In in-vitro experiments, the clotting time of GM/TCP@PEG was 15.43 s. Its clotting efficiency index was 4.79-fold that of uncoated microspheres and 15.8-fold that of commercial Yunnan Baiyao (YM). The clot mass was 1.63-fold higher than uncoated microspheres and 2.35-fold higher than commercial Yunnan Baiyao (YM). The shear strength measured on porcine skin reached 25.35 kPa, which was 5.39-fold that of the control group. The blood-derived hydrogel enabled sustained release of VEGF, PDGF-BB, and TGF-β1, promoting endothelial cell migration and tube formation. In vivo, GM/TCP@PEG microspheres achieved rapid hemostasis in rat liver, tail, and porcine liver/spleen hemorrhage models, and significantly enhanced bone regeneration via early vascularization in a rat critical-sized calvarial defect model. This blood-transforming strategy achieves synergistic hemostasis, adhesion, and pro-repair functions, provide a strategy with application prospects for tissue repair in complex hemorrhagic environments.