A　3D　model　is　established　to　simulate　the　bond　performance　of　corroded　RC　beams,　in　which　the　non-uniform　corrosion　of　tensile　reinforcement　and　confinement　conditions　(characterized　by　the　thickness-diameter　ratios　of　1.9-3.8　and　stirrup　confinement　index　of　0-8.3%)　are　investigated.　In　the　3D　numerical　model,　fine　modeling　was　adopted　to　consider　the　influences　of　corrosion　on　the　steel-concrete　interface　and　the　non-uniform　corrosion　was　considered　by　separating　the　tensile　bars　into　two　parts　with　inconsistent　diameter　loss.　Meanwhile,　a　two-stage　numerical　analysis　method　was　utilized,　to　reflect　the　corrosion-induced　concrete　cracking　by　applying　forced　displacement　and　subsequently　analyzed　their　flexural　bond　performance.　In　comparison　to　the　existing　experiments,　the　proposed　3D　numerical　model　is　proved　to　be　reasonable.　In　addition,　the　simulation　results　show　that　the　increment　of　the　(residual)　bond　strength　generated　by　the　increasing　thickness-diameter　ratio　increases　with　the　mass　loss　rate,　while　the　increases　of　stirrup　confinement　index　cause　much　more　increases　in　the　(residual)　bond　strength　for　the　corroded　RC　beams　than　the　un-corroded　beams.　Furthermore,　a　bond　stress-slip　relationship　is　proposed　taking　the　non-uniform　corrosion　and　confinement　conditions　into　account,　which　correlates　well　with　the　experiments.