A silane film was prepared on the surface of flaky FeSiCr powder by sol-gel method. The phase and morphology of the samples were observed by X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM), and the valence state and chemical composition of the elements were determined by X-ray Photoelectron Spectroscopy (XPS). The results showed that the observed images of homogeneous silane films confirm the successful preparation of lamellar FeSiCr@PFOTMS composites. The electromagnetic parameters measurement results showed that the complex permittivity of the samples is substantially reduced and the complex permeability changes little, then the balance of electromagnetic parameters is improved and the impedance matching is optimized. When PFOTMS is added in amounts up to 2 mL, the FeSiCr@PFOTMS composites showed the best microwave energy absorption and corrosion resistance. The minimum reflection loss value of the sample reached –32.22 dB at 2.16 GHz. The electrochemical test results showed that the open circuit corrosion potential of FeSiCr@PFOTMS composites with 2 mL PFOTMS increased from –0.217 V to 0.031 V, and the corrosion voltage increased from –0.215 V to 0.028 V. These results provide ideas for the preparation of multifunctional composites with both excellent microwave absorption properties and corrosion resistance in practical applications.