The controlled synthesis of mesoporous silica and metal oxide nanocomposites with a highly ordered porous structure and large specific surface area for specific applications has been an attractive topic in the field of porous materials. Herein, we introduce a novel method for the fabrication of highly ordered mesoporous structured and large specific surface area Fe2O3/SiO2 nanocomposites, and consider their application in room temperature gas sensors. The mesoporous Fe2O3/SiO2 nanocomposites were synthesised by a two-step method, which combines the hydrothermal growth of Fe2O3 nanoparticles and the microemulsion phase of Brij 56 (C16EO10) surfactant as templates in instantly direct-templating synthesis. This synthesis method enables the fabrication of mesoporous Fe2O3/SiO2 nanocomposites without distortion of the ordered porous structure after calcination at high temperature. The synthesised materials were found to be efficient in a room temperature VOC sensor application, with good recovery. (C) 2013 Elsevier B.V. All rights reserved.