Abstract: A multi-level modification strategy was adopted, which involved the construction of a core-shell structure, the introduction of magnetic components and the combination with a polymer matrix. Using glucose as the carbon source, SiC@C core-shell whiskers were prepared through a hydrothermal method and high-temperature sintering. These whiskers were then mixed with cobalt-based zeolitic imidazolate framework materials （Co-ZIF） in solution and sintered at high temperatures to prepare three-dimensional polyhedral microwave absorbing fillers. These fillers were subsequently mixed with polyvinylidene fluoride （PVDF） and hot-pressed to fabricate SiC@C/Co-Co₂Si@C/PVDF composites with different filler mass fractions （5%, 10%, 15%, 20%, 25%, and 30%）. The microwave absorption properties of the composites were investigated. The results show that with the increase of filler content, the dielectric constant of the composites increased, while the real and imaginary parts of the magnetic permeability remained at relatively low levels, and the dielectric loss tangent increased and was always greater than the magnetic loss tangent, suggesting that dielectric loss played a dominant role in the microwave absorption. When the filler content was 10%, the minimum reflection loss of the 2.41 mm thick composite reached −53.19 dB, and the effective absorption bandwidth was 7.64 GHz （10.28−17.92 GHz）, demonstrating excellent microwave absorption performance and impedance matching. For the 2.36 mm thick composite, the effective absorption bandwidth fully covered the Ku band （12−18 GHz） and partially covered the X band （8−12 GHz）, indicating good broadband microwave absorption adaptability across multiple frequency bands.