Abstract: The numerical modeling of the aircraft struck by high current pulse is studied based on transmission line matrix(TLM)to improve the protection performance of the aircraft against lightning indirect effects according to SAEARP5412 and 5416 relevant standards.Moreover,the fuselage surface current density, the transient electromagnetic field distribution inside and outside aircraft,the induced current in the onboard cable produced by the lightning stroke in different paths are discussed.Simulation results show that the method can effectively predict the lightning indirect effects of the metallic/composite aircraft,and then lighting electromagnetic pulse(LEMP)coupling mechanism of the aircraft,EM field distribution characteristics and cable coupling rules are analyzed.The numerical methods can be used for advanced research on the protection of the lightning indirect effects and related studies.