NaCrO2　is　a　promising　O3-type　cathode　material　in　sodium-ion　batteries.　However,　it　suffers　from　rapid　capacity　fading　due　to　the　unstable　structure　upon　cycling.　This　work　shows　that　in　situ　carbon　coating　during　the　synthesis　process　has　multiple　synergistic　effects　and　can　effectively　stabilize　the　material　structure　and　improve　the　cyclability.　It　is　found　that　sodium　vacancy　and　carbon　coating　in　NaCrO2　synchronously　occur,　which　improve　its　sodium-ion　transport　kinetics,　structural　stability　during　cycling　and　the　air　stability.　More　importantly,　the　strategy　is　universal　in　that　various　sources　of　carbon　display　similar　effect.　As　a　result,　the　asphalt-derived　carbon　coated　material　has　a　high　initial　capacity　of　129　mAh　g(-1)　at　0.1　C　rate　with　an　initial　Coulombic　efficiency　up　to　98.2　%.　In　addition,　it　shows　an　excellent　rate　capability　and　cycling　performance　with　81.1　%　retention　after　1000　cycles　at　5　C　in　half　cell.　Moreover,　a　full　cell　has　constructed　by　coupling　with　hard　carbon　anode,　which　shows　a　high　discharge　capacity　of　121.9　mAh　g(-1)　with　a　high　Coulomb　efficiency　of　94.7　%,　excellent　rate　capability　and　good　cycling　stability.　This　work　demonstrates　a　general　modification　method　on　NaCrO2　that　has　the　potential　for　practical　applications.