Background: HAV infection is still a common infectious disease, and can easily spread by the fecal-oral route, either via person-to-person contact or consumption of contaminated food or water. People at high risk of HAV infection include overseas travelers and workers from high endemic areas. HAV seroprevalence rate of international traveled healthy worker was not reported in Taiwan.Aim: Survey the prevalence of seroprevalence of hepatitis A antibody in overseas workers.Method: A total of 406 healthy overseas workers of three international companies during their annual health examinations were enrolled and examined for antihepatitis A virus IgG.Result: Of these 406 participants, 158 (38.9%) were found to be anti-hepatitis A virus IgG positive. The sero-positive rate of anti-HAV was significantly different between overseas workers aged below or equal to 30 years and those above 30 years (0% vs. 45.9%, p<0.0001). Conclusion:The vast majority of overseas workers aged ≤30 years are susceptible to HAV infection. Mass hepatitis A vaccination should be applied to overseas workers ≤ 30 years or that sero-negative for anti-HAV after screening.