Abstract: Some indexes such as mean skin temperature (TS), effective temperature, discomfort index (DI) and clothing index (CI) are able to quantilize the sensations of human to the heat in an environment with various combinations of air temperature, humility and wind. These indexes are analyzed in detail to show the specific scopes in which each index could work well respectively. The results calculated by those indexes with the meteorological data from Wuhan, are applied to compare with the synch ronic number of sunstroke among residents of the city. The demarcation of these indexes for the sensation of residents in summer are given based on the analyzes stated above. Finally the prediction problems of these indexes are discussed.