Arsenite　is　the　predominant　arsenic　species　in　flooded　paddy　soil,　and　arsenite　bioaccumulation　in　rice　grains　has　been　identified　as　a　major　problem　in　many　Asian　countries.　Lowering　arsenite　level　in　rice　plants　and　grain　via　accelerating　arsenite　oxidation　is　a　potential　strategy　to　help　populations,　who　depended　on　rice　consumption,　to　reduce　the　internal　exposure　level　of　arsenic.　We　herein　isolated　a　strain,　Achromobacter　xylosoxidans　GD03,　with　the　high　arsenite-oxidizing　ability　and　plant　growth-promoting　traits.　We　observed　that　arsenite　exposure　could　promote　A.　xylosoxidans　GD03　to　excrete　indole-3-acetic　acid　and　thus　promoted　rice　growth.　The　pot　culture　experiments　of　Indica　rice　cultivar　Guang　You　Ming　118　(GYM118)　demonstrated　that　A.　xylosoxidans　GD03　inoculation　of　paddy　soil　(4.5–180　×　108　CFU　GD03/kg　soil)　significantly　accelerated　arsenite　oxidation　in　flooded　soil.　The　daily　arsenic　oxidation　rate　with　GD03　inoculation　was　1.5–3.3　times　as　that　without　strain　GD03　inoculation　within　the　whole　growth　period　of　Indica　GYM118　in　the　presence　of　the　native　microflora.　It　thus　led　to　a　34–69%,　43–74%,　24–76%　and　35–57%　decrease　in　arsenite　concentration　of　the　stems,　leaves,　bran　and　grain　of　Indica　GYM118　respectively　and　a　59–96%　increase　in　rice　grain　yield.　The　paddy　soil　inoculated　with　40.0　mL/kg　of　A.　xylosoxidans　GD03　resulted　in　a　lowest　As(III)　concentrations　in　all　rice　organs　of　Indica　GYM118,　which　equivalent　to　only　24–50%　of　the　As(III)　concentrations　in　the　group　without　GD03　inoculation.　The　results　highlight　that　a　highly　arsenite-oxidizing　bacterium　could　accelerate　arsenite　oxidation　of　paddy　soil　when　facing　competition　with　the　native　microflora,　thus　decrease　arsenic　toxicity　and　bioavailable　soil　arsenic.　©　2020　Elsevier　Inc.