In this paper, the results obtained in the catalytic decomposition of methane in a fixed bed reactor using a NICuAl catalyst prepared by the fusion method are presented. The influences of reaction temperature and space velocity on hydrogen concentration in the outlet gases, as well as on the properties of the carbon produced, have been investigated. Reaction temperature and the space velocity both increase the reaction rate of methane decomposition, but also cause an increase in the rate of catalyst deactivation. Under the operating conditions used. the carbon product is mainly deposited as nanofibers with textural properties highly correlated with the degree of crystallinity. (C) 2008 Elsevier B.V. All rights reserved.