Abstract: To improve the protection performance of the helicopter against lightning, this paper builds a simulation environment in the CST Microwave Studio based on the transmission-line matrix method to simulate the UH-60 helicopter struck by high current pulse to study its lightning indirect effects according to SAE-ARP5416A. The distribution of the internal key cabin and the external electromagnetic field of the helicopter, the induced current in the onboard cable produced by the lightning in different paths are discussed. The simulation results indicate that using this simulation method, the helicopter indirect effects struck by lightning can be effectively analyzed and the results can guide the lightning protection design of the helicopter without developing the full-scale helicopter experiment.