In order to improve the interface compatibility between titanium alloys and hydroxyapatite ( HA) coating, a uniform HA coating was fabricated by electrophoretic deposition firstly, then the coating was treated in microwave at 1200 ℃ .Through the analyzing the phase structure of the coating, it is proved that a gradient coating is obtained by microwave inducement . The gradient coating is composed of oxide layer with TiO₂and TiO, CaTiO₃and a minute amount of HA. Because the gradient structure can alleviate the mismatch of thermal expansion coefficient between HA and titanium alloys, less cracks and higher bonding strength can be obtained.