Abstract: This paper analyzed the working TR module in lightning phenomenon and the thunder waveform. Combining its global position in system and port type in lighting environment, a new criterion for evaluating the lighting protection of RF circuit was proposed. Based on the environmental conditions and test procedures for airborne equipment, criterion for lighting protection in TR module design was established by combining voltage withstand and power capacitance performance, considering different level of lighting stroke. Moreover, this criterion is also researched for evaluating the received voltage and current value after a lighting protector in TR module. Finally, on basis of the filter characteristic, this paper provided an integral lighting preventer design method, which started form the thunder waveform to filter circuit response, then to the whole RF circuit design.