A numerical experiment was conducted in terms of a nested mode composed of Qian's prototype(1985)and Yan's model(1987)with an improved snowcover-albedo parameterization scheme introduced to investigated effect on east Asian atmospheric circulations of east/south in summer. Tibetan snow cover available in summer in an idealized condition. Evidence suggests that the model atmosphere is highly sensitive to the cover-caused thermal anomaly: the lowlevel altitude (the upper level altitude) is heightened (lowered) as opposed to the change in the corresponding surfaces in east China; cool summer and weakend summer monsoon circulation occur in much of east Asia; rainfall is greatly reduced from east China to south Janpan in contrast to the coastwise Huanghe-Huaihe plains and northern Xinjiang.