OBJECTIVE The objective of this cross-sectional study was to determine seroprevalence of hepatitis B surface antigen and related risk factors among new recruits in a military unit in Turkey. METHODS Eight thousand five hundred eighty-nine newly-recruited soldiers were enrolled in the study. Blood samples were drawn from them between January 2006 and December 2006 and ELISA technique was applied to the samples. In addition, questions on the risk factors of hepatitis B exposure were asked to the participants in the survey. RESULTS The results demonstrated that HBsAg seroprevalence was 2.8%. Further survey results indicated that seropositivity increased depending on certain risk factors. In multiple regression analysis, significant correlations were determined between HBsAg positivity and certain risk factors such as living in the Southeast Anatolia region (p<0.01), having a history of living with a hepatitis B carrier (p<0.001), and presence of a hepatitis B carrier in the neighborhood or at work (p<0.05). CONCLUSIONS The HBsAg seropositivity found in this study supports the fact that Turkey remains in the medium endemicity zone, and that horizontal transmission is predominant.