Hydrogen　can　be　produced　from　acetic　acid　(HAc)　derived　from　renewable　biomass　oil　via　auto-thermal　reforming　(ATR),　which　is　conducive　to　upgrading　current　energy　supply　in　a　carbon-neutral　and　clean　way.　However,　deactivations　caused　by　carbon　deposition,　sintering,　and　oxidation　have　been　long-standing　obstacles　for　nickel-based　catalysts.　To　address　these　challenges,　we　synthesized　a　series　of　Ni-Mg-Ti-O　catalysts　by　Pechini　method　and　tested　in　ATR.　Characterization　results　showed　that　mixed　oxide　of　Ni1-xMgxTiO3±δ　perovskite　was　formed　after　calcination　and　transformed　into　Ni0,　MgTiO3　and　TiO2　after　hydrogen　reduction,　while　the　Ti4+/Ti3+　redox　cycle　promoted　formation　of　oxygen　vacancies.　In　addition,　the　in-situ　evolution　of　MgTiO3　and　TiO2　into　MgTi2O5　during　the　ATR　reaction　was　proved,　which　suppressed　sintering　and　oxidation　of　Ni　species.　Density　functional　theory　(DFT)　study　confirmed　the　electron　transfer　over　the　Ni/MgTi2O5　interface,　as　well　as　the　enhanced　metal-support　interaction,　which　promoted　adsorption　and　dissociation　of　acetic　acid　molecules.　Consequently,　the　Ni0.08Mg0.10Ti0.37O0.92±δ　(N10MT)　catalyst　with　Ni/MgTi2O5　interface　showed　high　stability　and　activity　with　hydrogen　yield　at　2.72　mol-H2/mol-HAc.　©　2024