It’s possible that liquefaction and seismic collapse could occur during earthquake in high-humidity loess, which has been proved to be true both in laboratory dynamic test and investigation of paleo-earthquakes. At present, the code of engineering doesn＇t put the predictive judgment for the liquefaction of loess into consideration. In this paper, some cases of loess ground treatment are introduced, in which the treated saturated loess liquefied, thus the ground sank, caused by mechanical shaking or impact. It is meaningful to research on the liquefaction mechanization, liquefaction discrimination, harmfulness judgment and engineering precautionary measure for loess.