Results of studies on the activity of the Ni-containing catalyst in the steam reforming of methane (SRM) process are presented. It is established that the catalyst shows high activity in SRM, stability to coke formation and resistance to H2S presence in the reaction gas mixture. The catalyst was prepared on the basis of mixed oxides separated from layered vermiculite. The structure and the phase composition of catalytically active components were investigated by XAFS, XRD, EDX, TEM and Moessbauer spectroscopy. It is found that the active components of catalyst are represented by clusters with core-shell configuration where FeNi alloy is a core (similar to 10 nm) surrounded by superparamagnetic gamma-Fe2O3 shell (1-4 nm). These clusters are distributed in the mixed spinel Mg(Fe,Al)(2)O-4 matrix. It is suggested that clusters of FeNi alloy are active in SRM while superparamagnetic gamma-Fe2O3 particles are active in the oxidative decomposition of H2S. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.