Abstract: The traditional random coupling model sets boundary conditions at infinity in calculating the effect of electromagnetic pulse with the electronic equipment, which causes a problem named short-orbit effects. In order to decrease the effect existed in the traditional random coupling model, a short-orbit random coupling model (SORCM) of the two-port wave chaotic cavity is proposed by defining a short-orbit correction coefficient of the radiation impedance. The variation of root-mean-square error of induced voltage at the target point is analyzed with the largest short-orbit length. In different frequency range, the statistical characteristics and calculated results of the SORCM are compared with experimental data which can verify the correctness of the model. Theoretical analysis and experimental results show that the SORCM is more effective compared with the traditional random coupling model. It can be used to predict and analyze electromagnetic pulse effects of the complex electronic equipment.