Abstract: The continuing heavy precipitation is the most trigger factor for loess landslide. Continued heavy precipitation in the summer of 2011 in Guanzhong region caused the accumulation of rainfall up to the 50-return years, which triggered landslides resulting in many traffic disruptions and bringing a serious disaster. In particular, the Baqiao landslide occurred on the September 17(917Baqiao landslide) at the edge of Bailu highland. It had a total of 32 casualties. In order to reveal the causes and mechanism of the landslide and process motion, investigation and analysis of the917Baqiao landslide were implement to reveal disaster characteristics, triggered factors and formation mechanism. The landslide movement simulation was used to restore the process motion and disaster range. The results show that:(1)The landslide relative height is about 90m. The wide is 170m. Initiation average thickness is about 10m. The sliding direction is 55.The sliding distance is 150m. The total volume is about 15104m3. There is the three sliding cases with the sliding volumes are 9.5104m3, 3.5104m3 and 2104m3, respectively. The average deposit thickness is 12m. (2)It appears that the factors behind the 9.17 landslide in Bailu tableland are numerous and can be classified into three main categories. They are the long periods of heavy precipitation, slope cutting results in steepening of the slopes and the vertical joints in the loess. (3)According to the simulation results, the sliding process can be divided into 3 stages: the first stage is the start and accelerate stage(0～7.5s). The velocity is up to 4.9ms-1 and 8.4ms-1 form 0 in x-direction and y-direction, respectively. The sliding distance is 65m. The second stage is a speed reduction sliding(7.5～14s).The velocity is reduce to 1.5ms-1 and 2.5ms-1 in x-direction and y-direction, respectively. The sliding distance is 50m. The last stage is deposited and stoppage. The velocity is reduced to 0 and the deposited change to thin gradually. The sliding distance is 175m and the maximum deposit thickness is 14m. The simulation results are consistent with the field survey. The results provide important reference for understanding and studying mechanism of this type of landslide and also provide guidance for future disaster prevention and mitigation in this region.