Previously in our laboratory, electrolytic hydroxyapatite (HA)/TiO2 composite coatings have been successfully developed to improve the bioactivity and the bonding strength between Ti alloy and bone tissue. In this study, the top layer composed of collagen/HA composite was further deposited on post bioceramic (HA/TiO2) coated Ti alloy in order to improve bioactivity, the initial cell proliferation, and finally the osteointegration. Through X-ray diffraction, Fourier transform infrared, scanning electron microscopy/energy dispersive spectroscopy, inductively coupled plasma, electrochemical polarization tests, immersion tests, and cell culture including methyl thiazole tetrazolium and alkaline phosphatase assays, it was found that only the collagen could not be solely deposited by an electrochemical method, but it had been done with the codeposited HA; unstable octacalcium phosphate (OCP) was not found because the previous bioceramic coating preferred HA to OCP. The further deposition of the composite revealed the enhancing effects on bioactivity, proliferation, differentiation, and mineralization because the collagen contained in the composite not only retarded the ion release from the substrate but also provided an amino group to attract a biological protein for the first two, and the stable HA offered the excellent environment for the last two. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3525604] All rights reserved.