Theoretical calculations of chemical equilibrium were adopted to explore the syngas production of oxidative steam reforming of butanol (OSRB). The results indicated that when the H2O/C4H9OH molar ratio was 3 and the O-2/C4H9OH molar ratio was 1.5, the thermal neutrality temperature reached 602 degrees C, generating a corresponding H-2 yield of 59.3%, a CO yield of 39.5%, and reforming efficiency of 65.1%. Additionally, when the OSRB was at moderate temperatures (400-800 degrees C), adding an appropriate amount of O-2 effectively inhibited coke formation and exerted only a minor effect on butanol reforming efficiency. The analysis of the coking boundaries indicated that at the same H2O/C-1 molar ratio, alcohol fuels with higher carbon numbers (butanol > ethanol > methanol) produced higher degrees of coke formation. However, if OSRB was used, the amount of H2O and O-2 addition was able to be controlled to inhibit coke formation and reduce the coke formation zone considerably. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.