The composite coatings on commercially pure titanium substrate were prepared by micro-arc oxidation (MAO) in electrolytic solution containing calcium acetate and β-glycerol phosphate disodium salt pentahydrate (β-GP) adopting the fixed anode voltage of 450 V and the oxidizing time of 5 min. The effects of cathode voltage on phase and composition morphology of MAO films were investigated. The results show that: the surface of MAO films are uniform and the components of the films are composed of TiO2 and Ca3 (PO4)2 while cathode voltage varies from 100 V to 200 V. When cathode voltage is 300 V, the surface of the MAO films are destroyed and the predominant component is CaTiO3.