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Hexagonal boron nitride/silicon carbide (<i>h</i>-BN/SiC) ceramics were fabricated by a spark plasma sintering (SPS) method. Phase and microstructure of ceramics were characterized and observed, respectively, using the X-ray diffraction, scanning electron microscope and electron probe microanalysis. The effect of molar ratios of SiC to <i>h</i>-BN on the microstructure, relative density, hardness, thermal conductivity, and the heating rate by microwaves on the ceramics were investigated. The results showed that the orientation of flake-like <i>h</i>-BN was significantly influenced by SiC content in <i>h</i>-BN/SiC ceramics. With the increasing of SiC content, the <i>h</i>-BN flakes gradually became an isotropic distribution from the preferred orientation aligning in a SPS pressure direction. The relative density of <i>h</i>-BN/SiC ceramics was 97.6 &#177; 0.9% at a molar ratio of SiC to <i>h</i>-BN of 40/60 mol%. The preferential orientation of <i>h</i>-BN flakes contributed to a relatively high thermal conductivity along the SPS pressure direction, which was beneficial to increasing the heating rate of <i>h</i>-BN/SiC ceramics in microwave fields.