Transition　metal　dichalcogenides　with　high　theoretical　capacity　usually　suffer　from　poor　intrinsic　electronic　conductivity　and　drastic　volumetric　change　upon　cycling,　degrading　their　attractiveness　for　electrochemical　high-power　and　long-term　applications.　Herein,　a　high-efficiency　and　extensible　synthetic　strategy　for　in　situ　encapsulating　nanostructured　SnSe0.5S0.5　into　N-doped　graphene　(SnSe0.5S0.5@NG)　by　robust　interfacial　CSeSn　bonds　with　formation　of　3D　porous　network　nanohybrids,　is　reported.　Systematic　electrochemical　studies　indicate　that　interface　and　structure　engineering　on　SnSe0.5S0.5,　including　defects　implantation,　chemical　bonding　interaction,　and　nanospace　confinement　design,　endow　it　with　robust　structural　stability,　ultrafast　Na+　storage　kinetics,　and　highly　reversible　redox　reaction.　In　addition,　the　introduction　of　foreign　Se　ligand　not　only　facilitates　the　transport　of　electrons/ions　by　enhancing　the　conductivity　and　decreasing　the　diffusion　energy　barrier　but　also　generates　more　reactivity　sites,　as　demonstrated　by　density　functional　theory　calculations.　By　virtue　of　these　superiorities,　the　SnSe0.5S0.5@NG　exhibits　superior　sodium　storage　performance　with　high-rate　capability　and　long　durability　over　2000　cycles　at　2　A　g−1.　Impressively,　the　full　battery,　when　coupling　SnSe0.5S0.5@NG　anode　with　Na3V2(PO4)3/C　cathode,　can　deliver　high　energy　density　of　213 Wh　kg−1.　This　work　provides　an　effective　structural　engineering　strategy　to　design　advanced　electrode　material　with　potential　application　for　sodium-ion　batteries.　©　2022　Wiley-VCH　GmbH.