Abstract: On March, 2014, Hua-nancun Landslide occurred in Tianshui, Gansu Province, China. It is a loess-mudstone interface landslide which is caused by high pore water pressure of thawing of frozen perched ground water. The area of Hua-nancun landslide is 1.24104m2 and the volume is 1.24105m3. The retaining wall of the 310 national highway in K1428+10~K1428+210 was destroyed by Hua-nancun Landslide, and the road was always in a traffic jam because of 200m road was covered with the amount of accumulation on the 310 national highway since the landslide occurred. We investigated the Hua-nancun landslide in March, 2014; August, 2014; January, 2015, the landslide was in the activity all the time. Also detailed investigation about geological environment and characteristics of Hua-nancun landslide was done in the past time. The conclusion is obtained by studying the geological facters that frozen perched ground water is the main facter of producing Hua-nancun landslide. Continually heavy rain and artificial excavating are the inducing facters of Hua-nancun landslide on the same way.