Defects　have　been　regarded　as　playing　a　critical　role　in　the　functionalities　of　many　solid　dielectrics.　However,　the　contribution　of　defects　to　the　specific　coupling　between　strain　gradient　and　electric　polarization　(i.e.,　flexoelectricity)　has　not　yet　been　thoroughly　understood.　Herein,　we　selected　the　typical　ferroelectric　BaTiO3　(BTO)　ceramics　and　introduced　oxygen　vacancies　and　trapped　charge　defects　by　using　stoichiometric　and　nonstoichiometric　Fe　dopants,　respectively.　Compared　with　the　pure　BTO　ceramics,　the　flexoelectric　coefficients　of　stoichiometric　Fe-doped　BTO　ceramics　were　increased　by　fivefold　(from　9.5　to　65　μC/m)　while　that　of　the　nonstoichiometric　counterparts　almost　keep　stable.　The　results　show　that　the　oxygen　vacancies　rather　than　trapped　defects　make　a　remarkable　contribution　to　the　enhancement　of　flexoelectricity,　and　this　is　explained　by　the　reorientation　of　the　defect　dipoles　formed　by　the　oxygen　vacancies.　The　result　presented　in　this　work　not　only　benefits　the　understanding　of　the　mechanism　of　flexoelectricity　but　also　provides　a　feasible　strategy　to　design　flexoelectric　materials　and　related　devices　with　high　flexoelectric　coefficients.　©　2022　American　Physical　Society.