WOS: 000217248600003Objective: Hepatitis A is one of the most common infectious diseases in the world. The prevalence of hepatitis A virus (HAV) infection correlates with the economic development of a region due to the transmission by fecal-oral route. In this study, we aimed to determine the seroprevalence of hepatitis A among patients of different age groups admitted to a training and research hospital. Materials and Methods: During the study period, January 2009-June 2013, serum samples of patients admitted to Ahi Evran University Research and Training Hospital were tested for anti-HAV IgM and IgG antibodies by the chemiluminescent microparticle immunoassay using Cobas 6000 (Roche, Germany) analyzer. The patients were divided into the age groups: 0-5, 6-10, 11-20, 21-30, 31-40, 41-50, 51-60, 61-70, and 71 years and over. The statistical analysis was performed using SPSS 15.0 software and a p value of less than 0.05 was considered statistically significant. Results: Anti-HAV IgM and anti-HAV IgG positivity rates were 0.5% and 87.3%, respectively. The highest anti-HAV IgM positivity was detected in the 41-50 age group and the lowest in the 0-5 and 11-20 age groups. The highest anti-HAV IgG positivity rate was observed in patients 0-5 years of age (99.7%) and lowest in those 11-30 years of age (61%). Anti-HAV IgM positivity rate was highest in August, September and December. Conclusion: In this study, the prevalence of HAV infection was found to be similar to that in previous studies performed in our country. It is clear that implementation of vaccination programs as well as improving sanitation practices are essential for decreasing the prevalence of the infection