Rainfall is the main source of water supply, and the time and space distribution characteristics of it is one of the main reasons that composed of the temporal and spatial distribution characteristics [1]. The actual situation shows that in the same climate zone, the same river basin, rainfall is obviously variable in different time and space [2], especially in the mountain plateau, rainfall is significantly different in the factors as longitude and latitude, water system (reservoir, rivers, lakes), the run of the mountains, slope aspect and altitude change, it is the space variability of rainfall. The rainfall spatial distribution of some basin exists the obvious differences, especially in the dry regions [3]. The preliminary analysis of space variance is to understand the change rule of the natural factors in the changeable environment, so that it is good to the related research. The analysis research of the space variation law of rainfall is based on the actual observation rainfall **data** in a period, and to analyze the space mutation characteristics of the characteristic parameters, its own parameters and the relationship of all the parameters in the space. The rainfall distribution and the distribution of the vegetation have a lot of correlation, it is usually like that the area of higher plant coverage will have a corresponding rainfall, and the area with more rainfall, plant growth power and coverage rate in the ground is higher than that the less rainfall region [4]. In the mountains district, human activities attach more influence to the ground runoff, soil and water loss and landslide. Therefore, only if the spatial distribution law of rainfall fully understood in this area, that can be reasonable allocation and use of water, and give full play to the ecological and economic benefits of water resources, and do service for the human production and life.