Objective:To investigate the epidemiological characteristics of Coxsakievirus A16 (CVA16),and thus lay foundation for the comprehensive prevention and control of hand, foot and mouth diseases and development of CVA16 vaccines. Methods:Based on the active and passive surveillance systems built for enterovirus disease,we performed a surveillance of CVA16-associated diseases among 2 875 and 2 080 infants and young children from Donghai county and Baoying county,respectively,from March,2012 to February,2013. A unify investigation form was used to collect related information of CVA16-associated cases, and a series of throat and anal swabs were collected for real-time fluorescent quantitative PCR assay. Results:During the whole surveillance period, the incidence rates of CVA16-associated diseases were 16.73%(481/2 875) for Donghai County and 9.28%(193/2 080) for Baoying County. Only one peak of incidence, which occurred in May,2012,was observed in both counties. The addresses of reported CVA16-associated cases covered all towns in both two counties, but the incidence was different among different towns. All of the reported cases aged between 9 and 42 months. Although the sex ratios(male: female) were 1.59∶1 and 1.47∶1 for Donghai County and Baoying County,respectively,there was no significant difference of incidence between male and female in both two counties. Conclusion:From March,2012 to Feburary,2013,CVA16 was the major prevalent enterovirus in Donghai County and Baoying County in Jiangsu Province. The prevalence of CVA16 showed an obvious seasonal trend and regional difference.