Objective: To analyses the association between temperature, rainfall, relative humidity with rotavirus diarrhea among under 5 years old children, and provide theoretical basis for its scientific prevention and control. Methods: Data on rotavirus diarrhea and meteorology in Xiaoshan District from 2005 to 2019 was collected. Distributed lag nonlinear model (DLNM) was conducted to estimate the association between rotavirus diarrhea with meteorological factors, stratified by sex and age. Results: Low temperature (-3 ℃) and low relative humidity (46%) were found to be positively associated with rotavirus diarrhea[RR(95%CI)=1.60(1.31-1.96), 1.22(1.13-1.32)]. The incidence decreased with the increase of rainfall, relative risk of 25 mm were 0.66(95%CI=0.60-0.72) relative to 10 mm. Stratification analysis showed that girls were more sensitive to relative humidity than boys. Compared with children aged 0-2 years old, children aged 3-5 years old were more susceptible to temperature and relative humidity.In the case of extreme rainfall(>50 mm), with the increase of rainfall, the incidence of children aged 3-5 years with diarrhea continued to decrease, while that of children aged 0-2 years increased. Conclusion Low temperature, rainfall and relative humidity are associated with increased risk of rotavirus diarrhea in children, with gender and age difference, the impact of extreme weather on children health should be taken seriously.