This paper analyzed climatological characteristics of fog and its interaction with temperature and precipitation by methods of Man-Kendell trend analysis, abrupt change analysis and grey correlation analysis based on meteorological observations of fog, temperature, and precipitation from 1961 to 2016 in Xishaungbanna, southwest China. Results showed that, the fog mainly occurred in the early morning during the dry season in the study area. The frequency of annual fog days and annual cumulative duration of fog events decreased significantly at the significance level of 0.01, which was consistent with the insignificant decrease of precipitation, and opposite with the significant increase of temperature. The abrupt change time for annual fog days and cumulative duration of fog events were earlier than annual average temperature, but it was not obvious for annual precipitation, which suggested that fog was more sensitive to environmental changes than temperature and precipitation, and fog was one of the major indicators of environmental changes. Temperature, precipitation and fog events are closely related to each other in Xishuangbanna, which has less influences for the annual average temperature and annual precipitation on annual cumulative duration of fog than influences of annual cumulative duration of fog on annual average temperature and annual precipitation. The number of annual fog days was much affected by changes of temperature and precipitation. It has less influences for the annual fog days and annual cumulative duration of fog on annual precipitation than their influences on annual average temperature. The temperature was much affected by changes of fog events, and decreasing rainfall and rising temperature were not conductive to the formation of fog, which might result in a decrease of fog days and duration of fog events.