Abstract: This paper proposed an energy selective waveguide component (ESWC) for the protection of the front-end in the waveguide. The prototype adopted an array of PIN-loaded metasurfaces in the bottom wall and top wall of the waveguide. The status of these loaded PIN diodes is sensitive to the electric field in waveguide and could adaptively be switched, thereby achieve the power-dependent transmission coefficients. To verify the feasibility and performance, a prototype is designed and realized in the standard WR430 waveguide. Results of simulation and waveguide measurement show that on condition of incident power below 25 dBm, the insertion loss is below 1.5 dB in the frequency range from 1.8 GHz to 2.2 GHz; while with the level of incident power grows to 37 dBm and even higher, the shielding effectiveness increases to more than 20 dB in the central frequency. The agreement of results from simulation and measurement demonstrated the electromagnetic protection ability of the proposed ESWC.