The seroprevalence of anti-hepatitis E virus (HEV) IgG was investigated by using ELISA commercial anti HEV test kit in 408 healthy adults who lived in central part of Thailand, 168 of which were swine workers, 102 were poultry farmers and 138 were government officers. The overall rate of seroprevalence of IgG anti-HEV was 23.3 % (range 16.7-27.9%). The prevalence of anti-HEV antibodies in government officers was 16.7 % and in subjects from swine workers and poultry farmers who worked in farms for more than 2 years were 27.9 % and 24.5%, respectively. Although there was no difference in anti-HEV prevalence according to three job categories (p = 0.06) and to age groups (p = 0.4), but seroreactivity of anti-HEV in swine and poultry farmers were statistically significantly higher than those in officers (p < 0.01). From this preliminary study, HEV is supposed to be circulating in the central area of Thailand. It appeared that the probability of exposure and reinfection to HEV are higher in farmers than that in government officers. Poor environmental conditions in farms, occupation and low socioeconomic status might be risk factors in HEV infection.