Abstract: The"5?12"Wenchuan earthquake induced many secondary geological disasters.The Hongtupo landslide in southern Gansu took place in large-scale collapse and cracks during the earthquake.If the landslide was moved as a whole,then it would form a dammed lake.It seriously threats the safety of eighty hundreds people in place below the landslide.So,it is very important to adequately understand stability of the landslide and take effective emergency measures.Based on the geological environment where landslide located,a systematic research on characteristics and forming mechanism of the Hongtupo landside at Southern Gansu was achieved.The used methods includedregional geological investigation,measurement of micro physiognomy and failure and geophysical reconnaissance survey.The research results show that this landslide has the characteristics of remarkable classification and partitioning.The key elements of inducing this landslide to be revivable are rainfall,earthquake,river degradation and poor rock and soil mass engineering geological properties.Based on the landslide forming mechanism,using the method of transfer coefficient and so on,the stability states were evaluated by combination of qualitative and quantitative analysis on the conditions of natural state,rainfall and earthquake,respectively.The integrated control measures of prestressed anchor cable frame,blocking dam,draining and protective wall are put forward.