When finite difference （FD） method is used in modeling the propagation of seismic wave in 3-D viscoelastic complex media, it consumes vast quantities of computational resources. So on single PC or workstation, 3-D calculations are still limited to small grid sizes and short seismic wave traveltimes. In this paper, the parallel FD algorithm which based on a message passing interface（MPI） is introduced to solve above problem properly. Using PCCluster we can calculate the wavefield of the large 3-D viscoelastic complex models, furthermore predict and understand the kinematic and dynamic properties of seismic waves propagating through the models of the crust. It helps us in every stage of a seismic investigation.