Numerical modeling has long been recognized to be a powerful method of studying the wave propagation in media with complicated structures. More interests are aroused in the anisotropic problem and heterogeneous problem. The Pseudo-Spectral Method (PSM), with which global spatial derivatives are computed by multiplication in Fourier domain, is a new numerical modeling method based on the elastic wave equation developed in recent years. The main advantage of PSM is that it requires a relatively small number of grid points to achieve a specified accuracy. The PSM and its stability are presented. A 2-D PSM code based on workstation or PC is developed to model the 2-D elastic waves propagation in anisotropic/heterogeneous media.