Aims: To define HBV vaccination coverage among Mongolian healthcare workers. Introduction: Mongolia has a large burden of viral hepatitis, especially chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, which are associated with cancer and cirrhosis. The occupational risk for transmission of HBV, HCV and HIV among healthcare workers (HCWs) is well recognized. Methods: This is a cross-sectional hospital based survey which will be conducted among healthcare workers to evaluate HBV vaccination coverage and KAP towards to the HBV infection and vaccination. In total, 1200 health care workers were attended to the survey. Results: More than half of survey respondents were had full 3 doses of HBV vaccination. About 4.5% of them had infected with HBV. About 64.0% of them were health workers who are currently working at risk position and most of them had contact with blood, blood products and other body fluids, as well as the risk of needle-stick injuries. 40.0% of respondents who had full doses of HBV vaccination and 56.9% of them had immune due to natural infection. Whereas, 16.7% of respondents who did not received full doses of HBV vaccination were had immune due to natural infection. In general, 1 of 2 respondents had immune due to natural infection. Conclusions: The HBV vaccination coverage among health workers are relatively sufficient. However, already infected percentages of among health workers are high in Mongolia.