Objective: To analyze the disinfection quality and influencing factors of nurseries in Nanjing during 2019-2021, so as to provide a scientific basis for optimizing preventive disinfection strategies and measures in nurseries. Methods: Environmental samples from 389 nurseries in Nanjing from January 2019 to December 2021 were tested, and the change of disinfection quality qualification rate was compared. Results: The overall disinfection qualification rate of nurseries of year 2019-2021 were 96.32%, 95.85% and 94.60%, respectively, showing a downward trend ( χ 2 trend =8.67, P <0.05). Specifically, disinfection qualification rate of object surfaces, staff hands and tableware showed a downward trend, while the disinfection qualification rate of dynamic air showed an upward trend, and the differences were statistically significant ( χ 2 trend =23.17, 12.32, 5.37, 21.48, P <0.05). The total qualification rate of disinfection in Jiangning and Liuhe districts increased during 2019-2021( χ 2 trend =21.46, 24.05, P <0.05). Conclusion Disinfection quality of nurseries in Nanjing has declined by year during 2019-2021, especially the object surfaces and staff hands. It is urgent to optimize and refine the strategies and measures for preventive disinfection in nurseries, strengthen the training of personnel on disinfection knowledge, and ensure the quality of disinfection in nurseries.