The decomposition of methanol on Ni(1 0 0) surface has been investigated using DFT-GGA (density functional theory-generalized gradient approximation) method with the repeated slab models, and compared in detail with that on Ni(1 1 1) surface. The adsorption energies as well as the adsorbed structure for the possible adsorbed species involved in this reaction were obtained and compare to that on Ni(1 1 1). For the reaction path calculation, the DFT-GGA results showed that both of the C-H bond and O-H bond broken are the favorable reaction paths on Ni(1 0 0), which is different from the case of Ni(1 1 1) in which only the O-H bond broken is the perfected reaction path, suggesting methanol decomposition reaction may be a structure-sensitive reaction. It was also found that the rate-limiting step (RLS) is the abstraction of hydrogen from methoxy for the O-H bond broken pathways, and it is similar to the case of Ni(1 1 1). (c) 2006 Published by Elsevier B.V.