A　novel　non-stoichiometric　YxInO3+δ　(YIO-x,　0.8　≤　x　≤　1.04)　perovskite　catalyst　with　a　large　number　of　oxygen　vacancies　and　high　specific　surface　area　was　synthesized　using　glycine　self-propagating　gel　combustion.　It　was　found　that　low　levels　of　non-stoichiometry　in　the　A　site　of　YxInO3+δ　effectively　increased　the　amount　of　oxygen　desorption　by　39-42%　when　compared　to　the　original　(YIO-1)　due　to　Y-deficiency　and　oxygen　vacancies.　Further　investigations　showed　that　the　non-stoichiometry　also　brings　a　significant　change　to　the　Lewis　acid　sites　on　the　surface　of　the　sample,　which　confirmed　to　be　a　great　promoter　for　the　catalytic　combustion　of　methane.　In　addition,　the　catalytic　performance　increased　with　the　increasing　intensity　of　acid　sites.　After　50　h　of　the　stability　test,　the　catalysts　maintained　high　activity,　indicating　their　good　catalytic　stability.　©　the　Owner　Societies.