The　bond　behavior　between　steel　bar　and　concrete　is　greatly　affected　by　the　properties　of　the　concrete　material　and　rebar.　Compared　with　ambient　temperatures,　the　mechanical　characteristics　of　concrete　material　and　rebar　vary　greatly　at　cryogenic　temperatures　in　cold　regions.　To　investigate　the　bond　behavior　at　cryogenic　temperatures,　pull-out　specimens　were　simulated　considering　the　surface　characteristic　of　deformed　rebar　and　the　cryogenic　temperature　effects　on　the　mechanical　properties　of　materials.　In　the　model,　the　surface-to-surface　contact　interactions　were　adopted　between　the　interacting　sections.　The　studied　parameters　include　three　bond　lengths　(48,　80,　and　112　mm)　and　a　temperature　range　from　20　degrees　C　to　-120　degrees　C.　The　failure　process　at　cryogenic　temperatures,　final　failure　modes,　bond　strengths,　and　slip　were　investigated,　and　the　related　influencing　mechanism　was　analyzed.　The　numerical　results　demonstrated　that　the　increasing　bond　length　changes　the　failure　pattern　from　splitting　failure　to　pulling-out　failure　and　reduces　the　bond　strength.　The　bond　behavior　is　significantly　affected　by　cryogenic　temperatures　due　to　the　enhanced　strength　and　brittleness　of　materials.　The　damage　of　concrete　surface　in　bonding　area　at　cryogenic　temperatures　is　more　serious　than　that　at　ambient　temperature,　but　the　final　failure　mode　is　consistent.　The　bond　strength　and　bond　stiffness　are　enhanced　at　cryogenic　temperatures.　As　the　temperature　dropped　from　20　degrees　C　to　-120　degrees　C,　the　ultimate　bond　strength　improved　linearly　by　11.8%,　whereas　the　residual　bond　strength　and　ultimate　slip　decreased　linearly　by　51.3%　and　15.7%,　respectively.　According　to　the　numerical　results,　a　bond-slip　model　was　established　to　predict　the　bond　behavior　at　cryogenic　temperatures.　(c)　2023　American　Society　of　Civil　Engineers.