Light-weight, cellular β-SiAlON/SiC ceramics were produced via dip-coating of an Al/Si-powder containing preceramic polymer slurry into corrugated cardboard. The coated cardboard preforms were pyrolyzed in Ar-atmosphere at 1200°C, where the cellulose fibres decomposed into carbon. Simultaneously the Al/Si melt infiltrated into the porous carbon and formed β-SiC. Subsequent nitridation at temperatures between 1200–1530°C resulted in the formation of a β-SiC-containing $$\beta{-}{\rm Si}_{6-z}{\rm AI}_z{\rm O}_z{\rm N}_{8-z}$$ composite. Different pre-oxidation treatment resulted in a variation of the oxygen content in the solid solution phase (z = 0.6–1.2).