Abstract: High-intensity electromagnetic pulse can easily couple into the electronic system through antenna, cavity and cable, causing transient failure or permanent damage of the sensitive electronic equipment. Installing electromagnetic pulse protection circuit can effectively improve the anti-destruction ability of electronic equipment against high-intensity electromagnetic pulse. Herein, based on LC frequency selective network and transient voltage suppressor (TVS) diodes, we develop a wideband electromagnetic pulse protection circuit with outstanding suppression capability. The operation bandwidth of the protection circuit exceeds 2 GHz, while the insertion loss is less than 0.6 dB. Moreover, the suppression capabilities of this protection circuit towards square-wave pulse, wide-band high-power microwave and narrow-band high-power microwave were systematically investigated. The results show that the protection circuit has a suppression ratio of more than 40 dB and power capacity up to 387 kW, while the response time is as low as 0.7 ns. Altogether, the protection circuit has advantages of wide operation bandwidth, excellent suppression performance, fast response time and high power capacity, which are of great importance for the electromagnetic protection reinforcement of electronic information system.