Abstract: The effect of rainfall on landslide is a widely discussed topic.This paper expatiates the process of the action between the rainfall and landslide from some aspects such as the substance conditions and structure conditions that determine the stability,environmental conditions that affect the stability,rainfall,rainfall infiltration,rainfall density,and the variation of mechanical properties of soil,etc. We have accomplished the large scale field test of landslide inspired by artificial rainfall and laboratory soil test.The test results illustrate that there is a linearly descending relationship of the cohesion and angle of internal friction with the water content.The landslide inspired by rainfall mainly and other factors is a complex process.