A lot of geological disasters were triggered by the 2008 great Wenchuan earthquake. Massive loose deposits stayed in gullies and on the slopes surface in Yingxiu and they will develop into debris flows after rainfall events. In terms of the result of remote sensing interpretation of co-seismic landslide in 2008 and post-earthquake geological disaster in 2009, the susceptibility assessment of post-earthquake geohazard is analyzed through controlling factors, which conclude lithology, co-seismic landslide area density, slope, aspect, elevation, internal relief, distance to stream and stream power index. The study area can be automatically divided in to 193 catchments and reclassify each factor using hydrological analysis tools in ArcGIS platform. Calculating the CF value of each secondary classification through certainty factor method, then add all CF values together through ArcGIS platform to obtain the CF of each catchment. Another method is logistic regression model. Firstly, calculating the standardized value of each secondary classification factors. Then the regression coefficients of each factor are calculated by logistic regression through SPSS platform. Finally we can obtain the probability of each catchment. Ultimately the post-earthquake disaster susceptibility is divided ，into 5 categories considering the CF method and logistic regression equation, which include very high, high, moderate, low, and very low susceptibility. And results of ROC curves are 0.840 and 0.897 respectively，indicating that the accuracy of both two method meet the requirement.