Abstract: Due considerations have been paid to the characteristic features and phenomena of the tremendous loess landslides in crows induced by irrigated water. All of them occurred in Loess Plateau of China. Based on these features and phenomena, such as large extents, high-speed and long traveling distances, their universal law, mechanism, kinematical approach and slope stability are analyzed. A regional prevention rules that take drainage work as the dominant factor and the simple engineering preventions the second one is presented.