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Abstract: Composite materials consisting of ceramic monoliths and carbon nanofibres (CNFs) have been synthesized by catalytic growth of CNFs on the γ-alumina washcoating layer covering the walls of a ceramic monolith. The composites possess a relatively uniform mesoporous layer of CNFs of relatively small diameter. The thin alumina washcoating (ca. 0.1μm) prevents the CNFs from being trapped inside the alumina pores and hence the CNFs grow freely throughout the washcoating layer to form a uniform layer of CNFs that completely covers the surface of the monolith walls. The growth temperature is found to control the thickness of the CNF layer (2–4μm), the growth rate of the nanofibres, and the mechanical strength of the resulting CNF–monolith composite. At ideal conditions, a complete adhesion of the CNF layer and higher mechanical strength than the original cordierite monolith can be obtained. The CNF layer has an average pore size of 17nm with absence of microporosity which renders these monoliths promising candidates for the use as catalyst supports, especially for liquid phase reactions. The CNFs have small diameters (5–30nm) due to the high dispersion of Ni particles in the growth catalyst and the CNFs exhibit an unusual branched structure. [Copyright &y& Elsevier]