Abstract: Objective To analyze epidemiological characteristics and pathogen variation of hand-foot-mouth disease(HFMD)in Chifeng city of Inner Mongolia Autonomous Region and to provide references for making effective prevention and control measures for the disease.Methods Data on reported cases and epidemic pathogen detection of HFMD in Chifeng city from January 1st,2012 to December 31st,2015 were collected from National Disease Surveillance Information Management System and then analyzed with descriptive epidemiology methods.Results Totally 12 637 HFMD cases were reported in Chifeng city during the 4-year period and the average annual incidence rate of HFMD was 72.74/100 000;the annual HFMD incidence rate fluctuated,with the yearly rates of 75.28/100 000,59.32/100 000,106.75/100 000,and 49.43/100 000,respectively.Of all the HFMD cases registered,71.58%(9 045)were reported between May and August of a year;the majority of the reported HFMD cases were scattered living children aged 1-6 years;the male to female ratio was 1.29:1.Among all the HFMD cases,29 (0.23%) were severe incidents and 2 of the severe cases died,with a case mortality rate of 6.89%;the case mortality rate was 0.02% for all registered cases.Of all specimens sampled during the period,36.46%(733/2 005)were positive for enterovirus and of the positive specimens,36.46%,28.37%,and 50.34% were positive for enterovirus 71 (EV71),Coxsackie virus A16 (CoxA16),and other enterovirus,respectively.The pathogen most frequently detected among the registered HFMD cases was CoxA16 in 2012,EV71 in 2013,and other enteroviruses in 2014 and 2015.The distribution of pathogens detected in the registered HFMD cases significantly varied yearly (χ²=225.841,P<0.05).Conclusion The incidence rate of HFMD fluctuated at a high level and EV71,CoxA16,and other enterovirus were prevalent alternatively as dominant pathogens among the reported HFMD incidents in Chifeng city between 2012 and 2015.