In　this　study,　a　novel　composite　of　modified　diatomite　supported　nanoscale　zero-valent　iron　(mD-NZVI)　was　synthesized　and　characterized.　The　effects　of　four　factors　(mD-NZVI　dose,　temperature,　contact　time　and　initial　pH)　on　the　removal　of　Cr(VI)　by　mD-NZVI　were　studied　by　experimental　work　and　analyzed　by　response　surface　methodology　(RSM).　A　second-order　polynomial　equation　fitted　by　Box-Behnken　design　was　used　as　a　statistical　model　and　proved　to　be　precise　in　describing　the　significance　of　four　factors.　The　analysis　results　show　that　the　effects　of　four　factors　on　the　removal　efficiency　of　Cr(VI)　were　significant　(F　value　is　19.83),　initial　pH　was　found　to　be　the　key　factor.　In　addition,　the　effect　of　initial　pH　was　further　studied　and　the　maximum　removal　efficiency　of　89.34%　was　obtained　at　pH　of　3,　the　decrease　in　removal　efficiency　with　the　increase　in　pH　is　a　synergistic　effect　of　Cr(VI)　species,　surface　charge　of　mD-NZVI　and　OH-　amount　at　different　pH.