In this study, RGD peptide derived from extracellular matrix proteins was employed to modify the surface of yttria-tetragonal zirconia polycrystal (3Y-TZP) to promote cell adhesion. The surface of 3Y-TZP ceramic specimens was first modified using chemical treatment with aqueous solutions of H3PO4, CH3COOH, and NaOH, for the formation of Zr-OH surface functional groups. Then, the RGD peptide was immobilized on the surface of the 3Y-TZP through silanization method, with covalent bonding via the Zr-OH surface functional groups. From this study, the RGD peptide can successfully be grafted onto the chemical modified 3Y-TZP surface. The -OH functional groups formed on the surface of 3Y-TZP after acid/alkaline chemical treatment contribute to the grafting reaction of RGD peptides. The use of phosphoric acid solution in 3Y-TZP surface treatment before RGD peptide grafting for biomimetic modification can significantly enhance cell adhesion, proliferation, and differentiation. (C) 2015 Elsevier B.V. All rights reserved.