Abstract: A MonteCarlo program MCNP is used to simulate the energy deposition of high energy flux pulse electron beam in the target material. According to the simulation results and the size and the character of the hole on the tantalum target by electron beam bombardment, the basic physical destruction mechanism of structuredifferent tantalum targets is presented. Due to the difference of the energy deposition in different targets, the shock wave in the 1 mm solid target will develop and compress the target in both radial and axial directions, while the compression in the foil target is inapparent, the size of the hole on the 1 mm solid target almost doubles that of the foil target. The melt ejection and spallation in the theoretical model are in accordance with the experiment result．