Objective To analyze the epidemic characteristics of dengue fever in Mengla County and provide basis for scientific prevention and control of dengue fever.

Methods We collected the case information of dengue fever in Mengla County reported by the infectious disease reporting information system of China Center for Disease Control and prevention from January 1 to December 31， 2019 and the case field investigation records. The case data were analyzed by descriptive epidemiological method.

Results In 2019， Mengla County reported 369 cases of dengue fever， all of which were unclassified， including 354 clinically diagnosed cases， 15 confirmed cases， 6 severe cases， and there was no deaths. The annual incidence rate was 120.98/10⁵. Mengla Town had the most cases （145 cases， 39.30%） followed by 63 cases （17.07%） in Mengpeng Town. The reported cases were mainly local cases （65.85%）. The ratio of male to female was 1.25∶1. The age distribution was mainly in the group of 21‒60 years old （82.38%）. Farmers （112 cases， 30.35%） and business service providers （85 cases， 23.04%） were the majority. The annual cases were distributed from May to November， of which the most were reported in September， and the number of cases reported from July to October accounts for 93.22% of all cases.

Conclusion Mengla County is still a high incidence area of dengue fever in Yunnan Province， and the vector Aedes is widespread. It is suggested to strengthen mosquito prevention and control in the epidemic season， actively carry out patriotic health campaign， carry out special rectification of the environment in rural areas， and conduct effective public education.