To understand the genotype and the mutation of amino acid (aa) in the major hydrophilic region (MHR) of hepatitis B virus(HBV). The serum samples were collected from the surveillance of HBV among population in Henan in 2012. The S gene of HBV was amplified and sequenced. The acid amino sequences were analyzed with Mega6. 0 software. A total of 50 sequences of HBV S gene were contained, including 8 sequences of genotype B(16. 0%) and 42 sequences of genotype C (84. 0%). The main serotype of HBV among Henan population was adrq+ (84. 0%) . The mutation rate of T1261 was the highest (14. 0%). The overall prevalence of mutant strain of MHR was 24. 0% (12/50), and it was 37. 5% (3/8) for genotype B,21. 4% (9/42) for genotype C. HBV genotype C was predominant in Henan,followed by genotype B. The adrq+ serotype was predominant followed by adw2. The mutation of amino acid in,MHR of HBV was detected in this study. It is necessary to strengthen the surveillance for HBV mutation to provide accurate information during immunization process and HBIG therapy.