Abstract: Objective The study was conducted to investigate the epidemiological characteristics of outbreaks of infectious diseases in Zhenjiang of Jiangsu Province from 2004 to 2006. Methods The reported epidemics in the past three years were retrospectively analyzed. Results There were 77 reported epidemics from 2004 to 2006, including 13 entities of diseases and 1607 cases without death ones. The epidemics comprised mainly respiratory diseases, accounting for 92.21%, while chickenpox and mumps accounted for 28.57% and 19.48%, respectively. School epidemics accounted for 92.21%. Epidemics in March and April accounted for 54.55%. The most common single case was the epidemic influenza, involving 172 cases which accounted for 10.07% of the total number of cases. Conclusion The control work of epidemics in Zhenjiang City should focus on the respiratory diseases occurring at school in winter and spring, March and April.