The　residual　bearing　capacity　after　fire　is　of　great　significance　for　safety　assessment　and　repair　of　building　structures.　To　accurately　evaluate　the　residual　strength　of　corroded　beam　after　natural　cooling,　this　study　investigated　the　residual　bearing　capacity　of　corroded　beam　considering　the　bond　deterioration　after　fire　exposure.　First,　the　bond　behavior　and　flexural-deformation　capacity　was　conducted　by　pullout　test　and　bending　test　after　corrosion　erosion　and　fire　temperatures　damage.　The　bond　deterioration　test　shows　that　when　the　temperature　rises　above　200　degrees　C　and　the　corrosion　level　exceeds　4.3　%,　the　bond　strength　decreases　by　16.5　%.　At　the　temperature　reaches　600　degrees　C　or　the　corrosion　degree　reaches　13.8　%,　the　bond　behavior　damage　exceeds　50　%.　The　bending　test　indicates　that　corrosion　and　high　temperature　damage　both　decrease　the　bending　bearing　capacity　of　the　beam,　but　the　influence　of　high　temperature　damage　on　the　residual　bearing　capacity　is　greater　than　that　of　corrosion.　The　bond　property　deterioration　decreases　the　strain　value　of　the　tensile　rebar　during　the　bending　process,　and　decreases　the　bending　capacity　of　the　beam.　Finally,　a　bond-slip　constitutive　model　suitable　for　corroded　beams　after　fire　is　proposed,　which　is　applied　to　the　calculation　of　the　ultimate　moment　of　the　beam.　The　modified　value　of　beam　bearing　capacity　considering　bond　deterioration　has　better　collimation　and　higher　safety　margin.　The　bond-slip　constitutive　model　and　the　modified　calculation　method　of　bending　moment　of　beam　are　helpful　to　provide　more　accurate　performance　assessment　of　beam　after　the　coupling　effect　of　corrosion　and　fire　damage.