Abstract:The Northwest Loess Plateau is the most developed area of landslides in China, and precipitation is one of the main factors that cause loess landslides. The precipitation infiltration mode in loess aeration zone and the process and mechanism of causing loess landslides have been widely concerned for a long time. This paper takes the loess region of Gansu Province as an example. Through field investigation and comprehensive research, it is believed that there are various precipitation infiltration modes in the Loess Plateau influenced by landform, climate, precipitation type and other factors, and there are regional differences between precipitation infiltration modes and induced landslide characteristics in the Loess Plateau. In the loess hilly area with small precipitation, the surface runoff generated during rainstorm mainly infiltrates through the macro dominant channels such as sinkholes and joints and fissures in a short time, increasing the moisture content of loess, softening the loess body, reducing the stability of slopes, and finally causing loess landslides. In the loess tableland and loess wide flat area with large precipitation, atmospheric precipitation and irrigation water mainly recharge the loess phreatic water through the pores in the loess aeration zone in the form of areal long-term slow infiltration, and the continuous overcast rain in wet years can lead to mass loess landslides. The study has guiding significance for scientific setting of early-warning threshold of landslides caused by precipitation in the Loess Plateau.