Abstract: In electromagnetic engineering, the size of antenna can be reduced by the method of adding load and thereby the miniaturization design of antenna is realized. In this paper, a novel finite difference time difference(FDTD) method with lumped elements in the grids is proposed, in which the fine wire FDTD and lumped element FDTD are integrated together. As an example, the coupling problem of the lumped loaded linear antenna excited by intensive electromagnetic pulse is simulated and it is observed that the current responses of the antenna can be rapidly obtained. Then the correctness of the hybrid method is verified by comparsion with the simulation results of electromagnetic software based on the finite integral method. Finally the influences of the types and widths of electromagnetic pulses on the current responses of the antenna are analyzed and the results greatly help the protection design of antenna.