Abstract: In order to solve the shortcomings existed in available method to establish a numerical model of complicated terrain, a Matlab software programming based on the digital terrain map of the mining area was applied to the study on the method to establish the complicated terrain numerical model of mining area. A new method to establish a 3DEC numerical model was provided. The study results showed that the new method could be applied to the complicated terrain condition in any mining area. The practices showed that the method was high in the intelligent and fast in the modeling speed. The major operation procedures all were handled with the program module. The 3D surface graphics could be automatically drawn and the relevant format data documents would be automatically output. In the spline interpolation process, the distance between the lateral and longitudinal spline could be set up artificially in order to control the deviation between the surface model and the actual terrain. A comparison could be conducted between the established numerical model and the 3D surface graphics drawn with Matlab software and the reliability of established model was approved. Once the relevant program module could be slightly modified, the method could be applied to model established with the FLAC3D and other numerical simulation software.