A simulation analysis method of harsh electromagnetic irradiation susceptibility about electronics is proposed aiming for high electromagnetic pulse attack in complex electromagnetic environment. This method combines 3D electromagnetic field simulation with 2D electric circuit simulation, which includes steps of building model, defining material parameters, adding load and exciting source, placing observation points. This method can obtain time-domain and frequency-domain characteristic of space and cable. According to the simulation results, the voltage and current in space and cable can reach peak soon with broad frequency domain, which are able to destroy many electronics. Therefore, some methods should be adopted to protect electronic devices. The proposed simulation method also can be utilized to analyze harsh electromagnetic irradiation susceptibility of all common electronics.