History and Objectives: Due to prevalence of various types of viral hepatitis and the importance of its prevention and considering the different reports about the prevalence of type A hepatitis and lack of access to valid data in this region, in order to determine the prevalence of type A hepatitis this research was performed on three of fifteen years old patients with acute hepatitis who referred to Aboozar hospital of Ahwaz in 1376.

Materials and Methods: This study was performed by descriptive method on 90 patients with clinical and laboratory findings of acute hepatitis. Anti-HAV IgM was measured in serum specimens by ELISA method. Patient’s age and sex and the prevalence of hepatitis A in the specimens were evaluated and the confidence interval of its true prevalence was estimated with 95% probability.

Results: From the 90 patients with acute hepatitis, 84.4% had hepatitis A, its true prevalence in the society is estimated from at most 92% to at least 77%. 61.8% of patients with hepatitis A were boys and the remaining 38.2% were girls. The highest prevalence rate of infection, 37.4% was observed among three to six years old children. The prevalence of disease decreases with increasing age.

Conclusion: The prevalence of type A hepatitis is high in the population under study. Further research on defining the sources of transmission of infection in the region is recommended.