|Abstract: In order to study the multi-scale characteristics of drought and drought in the background area of Sichuan, this paper is based on the remote sensing monitoring of the monthly scale drought in Sichuan Province from July to August 2000-2015. In the background area of the geomorphology, the multi-dimensional analysis of the monthly average drought conditions in Sichuan Province and its evolution trend were carried out by using two-dimensional wavelet analysis method to study the average extent of drought conditions and the extent and extent of the trend in different topographic and geomorphological background areas. Further determine the driving factors that play a major role at each scale. This is to understand the multi-scale characteristics of the drought in this complex topographical background area in Sichuan, to determine the main scale range of the impact of different drought levels, and its main driving force. It is of great theoretical significance to propose different spatial regions and different spatial scales for drought prevention and drought countermeasures. Through the research, it is found that: 1) The average annual situation of drought conditions is the largest in the vertical direction, the second in the vertical direction, the second in the horizontal direction, and the smallest in the diagonal direction, reflecting the significant spatial differentiation of the drought along the vertical direction of the region. The dominant factor that leads to this phenomenon is the significant vertical gradient of vegetation. 2) The number and scope of the dominant scales of the annual average drought conditions in the background areas of different types of appearances are different. There are five dominant scales in the Chuandong Basin, and the medium-scale scales are most prominent in the macro-scale of 5040.75 km2. The severe drought and extra-large drought grades are dominated by the mesoscale (187.34, 560.08 km2), which is concentrated in the Chengdu Plain. A band. There are three dominant scales in the transition zone between the plateau and the basin. The macroscopic scale of 2194.5km2 is mainly characterized by moderate drought and has significant vertical differentiation. The mesoscale scales of 160.51 and 418 km2 correspond to severe or extraordinarily large droughts. The grade area is concentrated in the city and the built-up area. There are two dominant scales in the Western Sichuan High Principles. The macroscopic scale of 9487.5km2 is prominently represented in the diagonal direction as the drought-free area where the evergreen coniferous forest and the mixed forest in the central part of Ganzi Tibetan Autonomous Prefecture are interlaced; the mesoscale scale of 637.82 km2 is prominent in the horizontal and vertical directions. Grassland and mixed forest areas distributed along the horizontal and vertical directions in the northwestern part of the Tibetan and Qiang Autonomous Prefecture. 3) The three major topographical and morphological background areas, the number of dominant scales and the prominent scale characteristics of the drought and evolution trend are inconsistent. There are four spatial scales in the drought aggravation trend area in the Chuandong Basin, but the mesoscale scale is dominant, while the slowdown trend area is dominated by the macro scale of 5023.02 km2. There are mainly three drought-increasing trend areas in the plateau and basin transition areas. The dominant scale is also dominated by the mesoscale scale, while the slowdown trend area is more prominent with the three mesoscale scales. Although there are four dominant scales in the drought-increasing trend area of the western Sichuan Plateau, it is dominated by the macro scale. The mitigation trend area is dominated by the mesoscale. 4) Although the dominant scales of the various geomorphological background areas in the evolution trend of drought are different, they have strong positives in the causes of these scale characteristics, that is, they all show the trend of aggravation of drought and the decline of vegetation. The trend of change is dominant, while the area of drought slowdown is dominated by the increasing trend of precipitation.