The possibility of manufacturing thin foils of high-entropy alloys (HEA) of Co-Cr-Fe-Ni-Si system by the method of highspeed (up to 10 μm/min) electron beam physical-vapour deposition (EB-PVD) is shown in the work. It was established that silicon content in the alloy composition of approximately 5 wt.% improves the values of high-temperature resistance of basic CoCrFeNi HEA. It is shown that at soaking in air for 28 h at the temperature of 1000 °C the specific change in the weight of cocrfenisi 0.2 sample is not more than 0.9 mg/cm 2 . a technological scheme was proposed of manufacturing by welding three-layer thermal protection honeycomb panels with a low specific weight based on thin foils of high-entropy CoCrFeNiSi 0.2 alloy. It was found that the produced by the proposed scheme three-layer thermal protection panels can stand multiple thermal cycling from 25 to 1000 °c in air without the structure failure. the derived results can be the base for development of the technology of manufacturing lightweight honeycomb structures, capable of ensuring thermal protection of aerospace equipment elements at their interaction with the atmosphere.