Snow cover occasionally causes disasters, but it is an important water source for plants in Inner Mongolia steppe area, where wate is a restrict factor for plant germination, growth, and regermination. The objective of this research is to discover the impact mechanism of different levels of degrading Leymus chinensis and Stipa grandis steppe on snow cover and adaptation of plants under snow cover. The studied area is located in the typical steppe area of Inner Mongolia Xilingol League. It will include i)the of different levels of degeneration steppes on the physical properties of snow cover, the drifting and accumulation processes of snow, the freezing-thawing processes; ii) The impact of snow cover on the change of phenophase, growth and development processes, composition, and distribution pattern in the different levels of degradation steppes; iii) the correlation among snow-cover, snow drift process, water-heat effect,vegetation, and meteorological factors.This study could provide scientific basis for estimating the depth of snow cover, utilizing snow water resources, regulating snow cover, restoring vegetation, and controlling snow disasters.