A　NASICON-type　Mn/F　dual-doping　Na4Fe3(PO4)(2)P2O7　cathode　material　is　successfully　synthesized　via　a　spray　drying　method.　A　medium-spin　of　Fe　is　measured　by　DFT　calculation,　X-ray　absorption　near　edge　structure　(XANES),　temperature-dependent　magnetization　susceptibility　(M-T)　measurement,　and　electron　paramagnetic　resonance　(EPR)　tests.　It　indicates　that　the　eg　orbital　occupation　of　Fe2+　can　be　finely　regulated,　thus　optimizing　the　bond　strength　between　the　oxidation　and　reduction　processes.　Furthermore,　from　UV-vis　DRS　and　four-point　probe　conductivity　measurements,　it　can　be　seen　that,　after　adjusting　the　electron　spin　states,　the　band　gap　of　the　material　has　decreased　from　1.01　to　0.80　eV,　and　the　electronic　conductivity　has　increased　from　8.5　to　24.4　mu　S　cm(-1),　thereby　leading　to　competitive　electrochemical　performance.　The　as-optimized　Na4Fe3(PO4)(2)P2O7　displays　both　excellent　rate　performance　(121.0　and　104.9　mAh　g(-1)　at　0.1　C　and　5　C,　respectively)　and　outstanding　cycling　stability　(88.5%　capacity　retention　after　1000　cycles　at　1　C).　The　results　indicate　that　this　low-cost　Mn/F　dual-doping　Na4Fe3(PO4)(2)P(2)O(7)cathode　can　be　a　competitive　candidate　material　for　sodium-ion　batteries.