According to Berglund's formula (1983 ): W =(esk-ea)/essk-ea), the relative humidity of man's skin is calculated by means of the monthly mean value of air temperature,vapour pressue and skin temperature. The climate comfort belts are divided according to the relative humidity of the skin. It showed that the main factors which decided the distribution of the relative humidity of Chinese skin are latitude,distribution of sea-land, topography and atmospheric circulation. China's climate comfort belt is defined according to the relative humidity of the skin 25% - 45%.There are obvious regional difference and seasonal variance in the China's climate comfort belt.