Abstract: ObjectiveTo analyze the situation of hepatitis B virus(HBV)infection and vaccination and to evaluate the immunization effects after hepatitis B vaccine involved in the expanded program on immunization(EPI).MethodsA survey for 1 894 children aged 1-14 years old was carried out in national surveillance sites using multistage cluster randomized sampling method.Every child's hepatitis B immunization history and main risk factors were investigated through questionnaire.Venous blood samples were collected and tested for HBsAg,anti-HBs and anti-HBc by ELISA method.ResultsAmong the children the rates of hepatitis B vaccine inoculation and timeliness of birth dose in urban area were 97.13% and 78.43%,but the rates in rural area were 95.15% and 57.96%,respectively.The age standardized positive rates of HBsAg,anti-HBs,anti-HBc and HBV infection were 1.10%,70.02%,3.40% and 5.53%,respectively.ConclusionAchievement in hepatitis B control and prevention has been made in Jiangsu province since hepatitis B vaccine was brought into EPI.The positive rate of HBsAg was below 1% for children aged less than 5 years old.The rates of hepatitis B vaccine inoculation and timeliness of birth dose were increased.