Nanosized nickel ferrite/silica composites are synthesized using the sol-gel method. X-rays diffraction, Mossbauer and infrared spectroscopies, magnetic measurements and thermo-programmed reduction with hydrogen are used for their characterization. Significant differences in their catalytic activity and selectivity in methanol decomposition to CO and methane, depending on the ferrite/silica ratio, the annealing temperature and the phase transformations of the samples by the reaction medium are observed. (c) 2006 Elsevier B.V. All rights reserved.