In this study, to reveal the thermodynamic reaction mechanism and the conversion characteristics of material and energy for the steam reforming of multi-component materials, a chemical equilibrium model was constructed, and the reaction mechanism of the steam reforming of calcium carbide furnace off-gas (CCFG) was also identified. The conversion characteristics of material and energy were ascertained by assessing four independent reactions and their reverse reactions. And the effects of temperature, pressure and steam-to-gas ratio on the conversion ratios of CO and CH4, the yield of H-2 and the reaction heat were investigated. In addition, a method for determining the process parameters of steam reforming based on the follow-up utilization scheme of CCFG was proposed; the method involves using a four-panel diagram that plots parameters of the steam reforming process. Thus, the range of H-2/CO mole ratio that could be obtained from the equilibrium system of steam reforming of CCFG was determined. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.