Objective To analyze the data of suspected vaccination adverse reaction information management system (AEFIMS) in Suzhou City from 2014 to 2019,and analyze and evaluate the operation quality and monitoring data of AEFI. Methods Data of all cases reported by AEFIMS in Suzhou City from January 1,2014 to December 31,2019 were collected and analyzed by descriptive epidemiological method. Results A total of 2 898 cases were received from AEFIMS in Suzhou City from 2014 to 2019.All the four counties and one district under its jurisdiction reported AEFI,and the reporting rate of AEFI within 48 h was 100%; among 276 AEFI cases to be investigated,the investigation rate of AEFI within 48 h was 98.90%.The reporting rate of AEFI questionnaire within 3d was 98.19%.The classification rate of AEFI was 100%.The estimated reported incidence rate of the city was 23.92/100 000 doses,showing an increase year by year,including 2.12/100 000 doses of adverse reactions to vaccination and 0.23/100 000 doses of severe AEFI.The ratio of male to female was 1.31:1.AEFI was dominated by children under 1 year old,accounting for 75.94%.The number of reported cases in summer was the most (42.68%),followed by spring (22.43%),and the lowest in winter (16.29%) days,the general reactions were fever,local redness and induration.The common abnormal reactions were allergic rash,urticaria,maculopapular,vascular edema and febrile convulsion. Conclusion The AEFIMS is running well in Suzhou City,and the monitoring sensitivity and quality of AEFI are advancing steadily.There are no reports of vaccination accidents and vaccine quality accidents.The estimated incidence of adverse reactions to vaccination is within the expected range.