The aim of this study was to evaluate the efficacy of tenofovir in HBV patients at 12 months after treatment. A total of 122chronic hepatitis B patients who took tenofovir for at least 12 months were enrolled. We measured ALT levels, HBeAg, anti-HBe, HBV DNA, and serum creatinine at six and 12 months after treatment. The virological response rate at six and 12 months after treatment in naïve patients was 27.1% and 41.7%, respectively. High virological response rate at six and 12months after treatment showed an association with initial low HBV DNA titer and initial negative HBeAg status.