Abstract: In this psper, the effects of forest on ajusting temperature, increasinghumidity and intercepting precipitation, as well as its characteristics of sea-sonal and daily changes, are studied by using the meteorological data of themiddle-mountain humid evergreen broad-leaf forest and bare land outsideforest, measured from 1986-1987 in the natural conservation region of AilaoMountain(24 32'N, 101 01' E altitude 2450m).

Key words: Ailao Mountain, The evergreen broad-leaf forest, The characteristics of climate