Prussian　blue　analogs　(PBAs)　are　widely　considered　to　be　one　of　the　most　promising　types　of　cathode　materials　for　sodium　ion　batteries.　However,　unsatisfactory　structural　stability　upon　excessive　sodium　storage　and　long-term　cycling　is　still　a　bottleneck　in　industrial　applications.　Herein,　a　two-pronged　approach　of　single-crystal　and　high-entropy　PBA　(SC-HEPBA),　is　first　reported　to　solve　this　challenge　simultaneously　from　the　bulk　phase　and　interface.　The　nature　of　high　entropy　enables　the　unrestricted　Na+　diffusion　and　the　suppressed　metal　dissolution,　while　the　micrometer-sized　single　crystals　help　to　improve　the　tap　density　with　less　structural　degradation　upon　cycling.　As　a　result,　the　Na-rich　SC-HEPBA　with　an　intact　monoclinic　crystal　structure　delivers　a　high　capacity　of　115　mAh　g-　1　at　100　mA　g-　1,　outstanding　rate　performance　(i.e.　74.4　mAh　g-　1　at　3000　mA　g-　1)　and　good　capacity　retention　(79.6%)　over　1000　cycles　with　a　stable　operating　voltage　of　3.25　V.　The　SC-HEPBA/　NaTi2(PO4)3　full　cell　achieves　109.4　mAh　g-　1　and　a　stable　cyclability　over　2000　cycles　with　77.8　%　capacity　maintained.　The　proposed　two-pronged　approach　not　only　paved　the　way　for　the　practical　application　of　PBAs　in　SIBs　but　also　provided　guidance　on　inhibiting　the　structure　evolution　of　battery　materials　during　cycling.