Abstract: InSAR results' analysis assisted with GIS can give more comprehensive interpretation on surface deformation mechanism.In this paper,we present the methods to clip,split and merge SAR images with the help of GIS.Besides,the profile and contour analysis to SAR images are illustrated.In order to demonstrate the effectiveness on interpreting earthquake deformation mechanism using the InSAR results assisted with GIS,we analyze the Mw7.9 Wenchuan earthquake as follows.First,the seismic fault surface trace is extracted according to the InSAR range offset and coseismic deformation field.Second,through the comparison between the LOS deformation field obtained by geophysical forward using dislocation model and the InSAR coseismic deformation field,the whole and hanging wall corrections of InSAR deformation field are obtained,with which the more actual coseismic deformation are got by correction using GIS.Finally,more comprehensive analysis and interpretation on the characteristics of coseismic deformation are presented by using the 2D/3D coseismic deformation field,interferograms and profile analysis.