Transition　metal　sulfides　as　anode　materials　for　sodium-ion　batteries　(SIBs)　have　the　advantage　of　high　capacity.　However,　their　cycle-life　and　rate　performance　at　ultra-high　current　density　is　still　a　thorny　issue　that　limit　the　applicability　of　these　materials.　In　this　paper,　the　carbon-embedded　heterojunction　with　sulfur-vacancies　regulated　by　ultrafine　bimetallic　sulfides　(vacancy-CoS2/FeS2@C)　with　robust　interfacial　C-S-Co/Fe　chemical　bonds　is　successfully　synthesized　and　explored　as　an　anode　material　for　sodium-ion　battery.　By　changing　the　ratio　of　two　metal　cations,　the　concentration　of　anion　sulfur　vacancies　can　be　in-situ　adjusted　without　additional　post-treatment.　The　as-prepared　vacancy-CoS2/FeS2@C　anode　material　offers　ultrahigh　rate　performance　(285.1　mAh　g-1　at　200　A　g-1),　and　excellent　long-cycle　stability　(389.2　mAh　g-1　at　40　A　g-1　after　10000　cycles),　outperforming　all　reported　transition　metal　sulfides-based　anode　materials　for　SIBs.　Both　in-situ　and　ex-situ　characterizations　provide　strong　evidence　for　the　evolution　mechanism　of　the　phases　and　stable　solid-electrolyte　interface　(SEI)　on　the　vacancy-CoS2/FeS2@C　surface.　The　density　functional　theory　calculations　show　that　constructing　heterojunction　with　reasonable　concentration　of　vacancies　can　significantly　increase　the　anode　electronic　conductivity.　Notably,　the　assembled　vacancy-CoS2/FeS2@C//Na3V2(PO4)3/C　full-cell　shows　a　capacity　of　226.2　mAh　g-1　after　400　cycles　at　2.0　A　g-1,　confirming　this　material＇s　practicability.　The　carbon-embedded　heterojunction　with　sulfur-vacancies　regulated　by　ultrafine　bimetallic　sulfides　(vacancy-CoS2/FeS2@C)　is　successfully　synthesized　and　explored　as　an　anode　material　for　sodium-ion　battery.　The　mechanism　of　vacancy-CoS2/FeS2@C　for　sodium　storage　is　confirmed　by　in/ex-situ　measurements　and　DFT　calculations.　This　research　has　taken　an　important　step　toward　the　development　of　high-performance　energy　storage　electrode　materials.　image