Eight　beams　of　reinforced　concrete　were　prepared　to　investigate　the　deterioration　law　of　non-uniform　corrosion　on　the　bond　performance　of　steel　bar　and　concrete.　First,　the　corrosion　of　the　steel　bar　was　obtained　by　applied-current.　The　electricity　was　stopped　when　the　specimen　reached　the　designed　mass　loss　rate,　and　the　development　of　corrosive　cracks　on　the　concrete　surface　was　recorded.　Then,　three-point　bending　load　was　applied　to　the　beam　specimen　to　test　its　bonding　performance.　Finally,　the　corroded　steel　bar　in　the　bonding　area　was　taken　out　for　3　D　scanning　test　after　the　bond　failure　of　the　beam　specimen.　Test　results　show　that　the　volume　expansion　of　the　corrosion　products　of　the　steel　bar　caused　the　corrosive　cracks　in　the　concrete　protective　layer　along　the　axis　of　the　longitudinal　tensile　bar,　and　the　maximum　corrosive　crack　widths　on　the　concrete　surface　had　a　logarithmic　relationship　with　the　mass　loss　rate　of　the　steel　bar.　There　were　rust　pits　on　the　surface　of　the　corroded　steel　bar,　and　as　the　mass　loss　rate　of　steel　bar　increased　to　10.　3%,　the　total　length,　width,　and　depth　of　the　rust　pits　increased　by　68.　27,　40.　2　1,　and　9.　98　mm,　respectively,　suggesting　that　the　total　length　of　the　rust　pits　had　the　most　significant　increase.　On　the　basis　of　the　test　results,　a　relative　bond　strength　degradation　model　of　steel　bar　and　concrete　was　established　in　consideration　of　the　influence　of　non-uniform　corrosion.　According　to　the　correlation　between　the　mass　loss　rate　and　the　maximum　corrosive　crack　width　on　the　concrete　surface,　a　calculation　model　of　relative　bond　strength　based　on　the　maximum　corrosive　crack　width　on　the　concrete　surface　was　proposed　and　verified.　©　2022　Harbin　Institute　of　Technology.　All　rights　reserved.