It is important to investigate and evaluate the stress-deformation relation and fracture behavior of discontinuous surface of rock masses during shear process. Therefore, this paper firstly obtains the residual geometrical information of rock discontinuous surface after block shear test in-situ, through measuring rock discontinuous surface with special-designed laser scanning system. Then, by implanting GIS technology, the morphology of rock discontinuous surface can be conserved as digital data in GIS database management system. Furthermore, this paper proposed the new analysis method for simulation of shear process in the rock discontinuous surface through the use of the TIN and GRID models of GIS. The simulating and visualizing results show that this analysis method can tolerably quantify the change of fracture region and distribution of inner stress during shear process.