Catalytic steam reforming of liquid fuels such as kerosene is an important route for hydrogen production for the fuel cells. However, there is serious catalyst deactivation due to the carbon deposition on the catalyst. In this study, in order to develop a catalyst that has superior catalytic performance for steam reforming of kerosene, 12SrO-7Al(2)O(3) (S12A7) that can incorporate active oxygen ions into the nanocage, was paid attention as a support material, subsequently steam reforming of dodecane and toluene as kerosene model compounds was performed over various Ru/SrO-Al2O3 catalysts with S12A7 phase. The Ru/SrO-Al2O3 catalysts with high S12A7 content exhibited higher catalytic activity than a commercial Ru/Al2O3 catalyst, despite low Ru loading and Ru dispersion. The S12A7 content in the SrO-Al2O3 support was remarkably affected by the calcination conditions such as temperature, moisture, and cooling rate. The S12A7 content was the highest in the SrO-Al2O3 support calcined at 873 K in a stream of moist nitrogen (p(H2O): 1.9 kPa). The turnover frequency (TOF) for steam reforming of dodecane over Ru/SrO-Al2O3 catalysts exponentially increased with an increase in the S12A7 content. This result indicates that the active oxygen species in S12A7 contribute to the acceleration of oxidation of CHx species on Ru metals. (C) 2015 Elsevier B.V. All rights reserved.