Objective: To analyze the epidemiological characteristics, etiological distribution and risk factors of recurrent hand, foot and mouth disease (HFMD) in Jiaxing City, so as to provide scientific evidence for developing targeted prevention and control strategies. Methods: Based on the China Disease Prevention and Control Information System, data of all reported HFMD cases in Jiaxing City from January 1, 2016 to December 31, 2024 were collected. Epidemiological and etiological distribution characteristics of recurrent HFMD cases were described. The Kaplan-Meier method was applied to estimate the cumulative risk probability of reinfection, and the Cox proportional hazards regression model was used to identify risk factors for HFMD reinfection. Results: A total of 3 105 recurrent HFMD cases were reported in Jiaxing City during 2016-2024, with a reinfection rate of 3.99%. The majority of reinfections were second episodes (97.68%). HFMD reinfection was associated with sex, age, population category and etiological serotype ( χ 2=26.44, 609.92, 459.72, 32.01, all P <0.01). The incidence of recurrent HFMD exhibited a bimodal seasonal pattern, with peaks occurring from June to July and September to November. Spatial distribution indicated that Nanhu District, Jiashan County and Tongxiang City accounted for 49.02% of all recurrent cases citywide. Among 264 laboratory confirmed recurrent cases, EV-A71 was the predominant pathogen (29.92%). The proportion of EV-A71 showed a trend of initial decline followed by rebound, while the proportion of CV-A6 increased over time ( χ 2 trend =6.94, 47.43, both P <0.05). Of 51 patients with ≥2 etiological test results, 56.86 % experienced reinfection with a different serotype. The median time to HFMD reinfection was 17.23 (0.50, 105.03) months after the primary episode. The reinfection probability was 0.61% at 6 months, 3.68% at 36 months, and remained approximately 5% at 64.37 months. Multivariate Cox regression revealed that male sex ( HR =1.23), age ≤ 3 years ( HR = 1.84), and scattered children and preschool children ( HR =3.78, 3.47, respectively) were independent risk factors for HFMD reinfection (all P <0.05). Conclusions Recurrent HFMD in Jiaxing City presents temporal and population heterogeneity, and its etiology shows an alternating serotype evolution pattern. Enhanced surveillance should be implemented among priority populations and high incidence regions, and multivalent vaccines should be developed to confer broader protection.