Micro Arc Oxidation (MAO) process was utilized to fabricate nano bioceramic TiO 2 –hydroxyapatite coatings on titanium substrates. Samples were produced in electrolytes contained 1g/l β-glycerophosphate and 5, 10 and 15g/l calcium acetate for 3, 6 and 10min at 350V. The techniques including XRD, XPS, SEM, FESEM and EDX were employed to study the effect of processing parameters. Hydroxyapatite, anatase, α-tri calcium phosphate and calcium titanate phases as well as 30–60nm-size crystals were detected in the coating layer. It was also observed that the pore volume would increase by increasing the electrolyte concentration. The growth time was also found to influence the total pore volume. Furthermore, the individual pore sizes would also be increased as the arcing time increased. By increasing the electrolyte concentration and growth time, the rougher surface layers were obtained. Depending on the growth time and electrolyte concentration, pore size and density were measured 0.303–1.77μm and 10.7–17.3%, respectively.