Ultrastrong,　biomorphic　cellular　silicon　carbide　(bio-SiC)　ceramics　were　generated　by　the　carbothermal　reduction　of　gaseous　SiO　with　a　pyrolytic　carbon　template.　The　anisotropic　wood　tissue　microstructure　is　replicated　in　the　bio-SiC　materials,　in　which　almost　fully　dense　cell　walls　are　assembled　by　directional　columnar　SiC　nanocrystalline　structures　that　are　100-200　nm　in　diameter　and　100-500　nm　in　length.　The　resulting　bio-SiC　ceramics　exhibited　high　porosity　(76%∼86%),　superior　flexural　strength　to　other　materials　(σ||　≈　38.3　MPa),　high　thermal　dissipation　characteristics　(kτ　≈　10.3　W·m-1·K-1　at　room　temperature),　and　high　anisotropic　thermal　conductivity　(kτ/k||,　â＇¼1.6).　The　orientation　dependence　of　the　microstructure-property　relations　may　offer　a　promising　perspective　for　the　fabrication　of　multifunctional　ceramics　and　composites.　©　2019　American　Chemical　Society.