Abstract: Magnetic carbon nano-onions (MCNOs) and multi-wall carbon nanotubes (MWCNTs) were prepared by chemical vapor deposition using a stainless steel mesh as the substrate and a sol-gel derived LaFeO₃ as the catalyst. They were dispersed in water with a mass ratio of 1:1, and spray-dried with the assistance of ultrasonication to form hybrid granules. The morphology and magnetic permeability of the granules were investigated by XRD, SEM, TEM, Raman spectroscopy and a vibrating sample magnetometer. The granules were coated on a glass plate to evaluate their microwave absorption properties with a microwave vector network analyzer. Results showed that the absorption ability of the hybrid granule coatings was significantly improved in the frequency range 2-18 GHz compared with MCNOs or MWCNTs alone under the same conditions. With an increase of the coating thickness, the maximum absorption peak shifts to a lower frequency. The coating shows the best absorption properties when the thickness is 3.5 mm, where the maximum peak value reaches -25.6 dB and the effective bandwidth of less than -10 dB reaches 2.2 GHz.