Abstract: We simulate the electromagnetic radiation calculation based on the multi-core CPU cluster parallel structure by using MPI+OpenMP hybrid parallel algorithm.This is an effective solution to the traditional FDTD method in the calculation of the electromagnetic radiation on the problem of inadequate large data space and time.What is more,we by means of regional segmentation,sub-regional data communications,consolidation and other methods to improve procedures nested parallelism,and finally verify the correctness of the calculation results.According to compare the computational time with MPI Algorithm on the high performance computer of Shanghai University,We draw the conclusion that The MPI+OpenMP hybrid parallelized code is indicated to be practical in achieving high speedup and great runtime reductions.