Objective To study the relationship between scarlet fever and meteorological factors in Minhang District， Shanghai， and provide scientific basis for prevention and control of scarlet fever and establishment of a scarlet fever early warning system.

Methods Data of the a scarlet fever epidemic were obtained from China Disease Control and Prevention Information System， and the meteorological data were obtained from Shanghai Minhang Meteorological Bureau. A generalized additive model was used to explore the relationship between scarlet fever incidence and meteorological factors in the R3.6.1 software.

Results Between 2009 and 2020， there was a rapid increase in the incidence of scarlet fever starting from 2011. There was a negative correlation between scarlet fever and wind velocity： the higher the wind velocity， the fewer cases. The correlation of number of cases with air temperature and atmospheric pressure was non-linear. The number of scarlet fever cases was positively correlated with air temperature below 17 degrees Celsius， and negatively correlated with air temperature above 17 degrees Celsius. The number of cases decreased with the increase of atmospheric pressure when atmospheric pressure was less than 1 017 MPa， and increased with the increase of atmospheric pressure when atmospheric pressure was more than 1 017 MPa.

Conclusion The incidence of scarlet fever is negatively correlated with wind speed， which can be reduced by opening windows for ventilation. The incidence of scarlet fever has a nonlinear relationship with air temperature and air pressure. The findings of this study provide scientific information for better understanding the epidemic trend of scarlet fever in Minhang District， contribute to the establishment of an early warning system， improve the active prevention and intervention of risk factors of the disease， and reduce its social burden.