The incorporation of osteoinductive molecules onto the surface of biomedical substrates is clinically crucial for achieving the desirable osteointegration of orthopedic implants. Here, a simple biologically inspired coating process originating from the polymerization of dopamine was used for efficiently improving cell-adhesion and osteogenesis of hydroxyapatite and poly(lactide-co-glycolide) (HA/PLGA) composite materials. Arg-Gly-Asp peptide (RGD) and BMP-2 peptide (derived from osteogenic growth factor bone morphogenetic protein-2) were simultaneously loaded onto the surface of HA/PLGA composite substrates under alkaline conditions for dopamine polymerization. The obtained results indicate that the active coating layer of RGD and BMP-2 peptides could significantly facilitate cell adhesion, cellular osteogenic differentiation and calcium mineralization of mouse pre-osteoblasts. Furthermore, the implantation of peptide coated HA/PLGA porous scaffolds enhanced osteogenesis in vivo for the repair of rabbit radius defects. It is predictable that this peptide biofunctionalized coating process can be utilized to enhance the understanding of osteoinduction and develop novel bone implants.