Abstract: Aiming at the problem that high altitude nuclear electromagnetic pulse(HEMP) protection index of integrated radio frequency system cannot be decomposed into each component equipment in engineering design, the coupling of HEMP to the integrated radio frequency system(IRFS)is studied. A multi-channel coupling analysis and verification method is adopted. The HEMP coupling of VHF antenna, HF antenna, L band antenna, frame and interconnected cable in the IRFS is simulated and analyzed, and corresponding tests in the bounded wave HEMP simulators conducted. Simulation and test results show that the most important channel for HEMP coupling to IRFS is the VHF antenna, and the maximum coupled voltage is up to 800 V. The secondary channel is the aperture of the non-metallic connector of the IRFS rack module, and the maximum coupled voltage of the aperture is up to 100 V. The coupling voltage of the cable can be ignored. These coupling voltage indices can be used as engineering protection design indices for airborne IRFS, and be decomposed into various antennas and modules.