Objective : To assess the impact of inclusion of hepatitis A vaccine in Expanded Program on Immunization（EPI）on hepatitis A incidence. Methods : The data of patients with hepatitis A from 1998 to 2017 in Huzhou were collected through Huzhou Infectious Diseases Yearbook and China Disease Prevention and Control Information System. Interrupted time-series models were constructed using the year 2008 when hepatitis A vaccine was included in EPI as the intervention time point. The influence of hepatitis A vaccine into EPI on the hepatitis A incidence was evaluated by analyzing the changes in the level and slope of incidence before and after hepatitis A vaccine into EPI. Results : Before the inclusion of hepatitis A vaccine in EPI,the average annual incidence rate of hepatitis A was 10.228/100 000 and the incidence of hepatitis A showed a significant descending trend with an annual decrement of 1.558/100 000. After the inclusion of hepatitis A vaccine in EPI,the average annual incidence rate of hepatitis A was 1.721/100 000 and the incidence of hepatitis A showed a significant descending trend with an annual decrement of 0.263/100 000. The average annual rate of decline in the hepatitis A incidence decreased by 1.295/100 000 after the inclusion of hepatitis A vaccine in EPI. Conclusion The incidence of hepatitis A significantly reduced after inclusion of hepatitis A vaccine in EPI,and the EPI strategy had a continuous effect on the decreasing trend of hepatitis A incidence.