Abstract: Objective To understand the main characteristics of concentrated outbreak of influenza in schools and childcare institutions in Guiyang city, so as to provide relevant effective basis for better targeted prevention and control.Methods Descriptive epidemiological methods were used to analyze the influenza cluster outbreaks in schools and childcare institutions in the city from 2016 to 2018.Results A total of 38 influenza outbreaks occurred in schools and nurseries,35 occurred in primary and secondary schools(92.10%). There were 1 case in university(2.63%) and 2 cases in childcare institutions(5.26%). The outbreaks were concentrated in autumn and winter(76.32%). There were 530 cases of influenza cluster epidemic. 45 329 people were affected by the epidemic,and the incidence rate was 1.55%,1.05% and 5.50%,in 2016-2018,respectively. The highest incidence was in 2018(5.50%). No critical cases or deaths occurred in the past three years. There were statistically significant differences in the incidence rate of influenza cluster cases(χ²= 32.156,P<0.05) among different years.Conclusion Schools and nurseries are places with high incidence of influenza cluster. Early detection,early reporting and early treatment of influenza cluster outbreaks should be carried out,and good health habits should be cultivated through publicity and education. Influenza vaccination should be given to improve the immune level of the population.