Nickel-based　catalysts　exhibit　excellent　initial　activity　in　the　auto-thermal　reforming　(ATR)　of　acetic　acid　(HAc)　to　produce　hydrogen;　meanwhile,　deactivation　issues,　namely　oxidation,　sintering　and　carbon　deposition,　have　not　been　fully　addressed.　Hence,　we　prepared　a　series　of　Ni-W/SiO2　catalysts　and　found　the　Ni-2W/SiO2　catalyst　with　2　wt%　W　decoration　presented　the　best　catalytic　activity　and　stability:　the　conversion　rate　of　acetic　acid　was　stable　at　100　%,　and　the　hydrogen　yield　remained　at　2.8　mol-H2/mol-HAc　with　neither　sintering　nor　carbon　deposition.　The　excellent　catalytic　performance　of　Ni-2W/SiO2　was　analyzed　and　can　be　attributed　to　the　special　properties　of　WO2　as　followed:　First,　during　the　ATR　process,　WO2　species　migrated　to　the　surface　of　Ni　phase　and　formed　an　interface,　which　resulted　in　strong　interaction　of　WO2-Ni　and　relieved　carbon　deposition　and　sintering　of　Ni　species;　Second,　the　effect　of　electron　donor　by　WO2　species　on　the　WO2-Ni　interface　during　the　reduction　procedure　was　found　and　preserved　a　stable　proportion　of　Ni0　active　species　during　the　ATR　process;　Third,　DFT　and　in-situ　DRIFTS　confirmed　that　CH3COOH　tends　to　be　enriched　on　the　WO2　species　of　the　WO2/Ni(1　1　1)　interface　rather　than　on　the　Ni(1　1　1)　surface,　promoting　the　adsorption　and　dehydrogenation　of　CH3COOH　to　intermediates　of　CH3COO*　and　H*,　which　is　difficult　to　occur　on　WO3　species　of　the　WO3/Ni(1　1　1)　interface　because　of　high　reaction　barrier.