An objective of the study was to determine the changes in the risk of developing hepatitis A in the 30-years period and discuss the need for vaccination against HAV infection in Croatia and the city of Rijeka comparing incidence of hepatitis A between 1970-1974 and 2000-2004 periods. Hepatitis A declined in both populations and affected more prominently older population groups. Improvement of hygiene and sanitary conditions appears to have decreased hepatitis A incidence among children and adults, but only a seroepidemiological study can give more accurate data as a basis for discussion on the necessity of vaccination as a further measure in reducing hepatitis A incidence.