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This study was performed to investigate whether the bioactivity of the anodized and hydrothermally treated Ti-6Al-7Nb alloy were affected by the process conditions of anodic oxidation. Anodizing was performed at a current density of 5~50 mA/cm2 in up to 240~300 V in electrolyte solutions containing DL-α-glycerophosphate(DL-α-GP) and calcium acetate (CA). Hydrothermal treatment was done at 300oC for 2 hours to produce hydroxyapatite (HA) for bioactivity. Bioactivity was evaluated from surface activation layer formed on the surfaces in a Hanks' solution with pH 7.4 at 36.5oC for 30 days. The size of micropores and the thickness of oxide film were increased by increasing the spark forming voltage, and more complex oxide layers were formed. HA crystals were observed on the anodic oxide film after hydrothermal treatment at 300oC for 2 hours. The anodic oxide films were composed of strong anatase peak and rutile peak, and showed the increase in intensity of anatase peak after hydrothermal treatment. When electrolyte composition, voltage and current density were increased, the deposited HA crystals showed a fine shapes. Bioactivity in Hanks' solution was accelerated when the oxide films were composed of strong anatase peak with rutile peak. Oxide layers selectively showed surface activity at the pertinent electrolyte composition. When voltage and current density were increased, the surface activity was increased. The amount of Ca and P was increased in surface having bioactivity in Hanks' solution.