Impact　(or　blast)　and　fire　always　take　place　concomitantly　and　threaten　the　service　life　of　engineering　structures.　Combined　effect　of　high　temperature　and　strain　rate　on　the　mechanical　behaviors　of　reinforced　concrete　(RC)　structures　has　attracted　much　attention　of　researchers.　In　this　work,　a　three-dimensional　meso-scale　simulation　method　was　established　to　study　the　combined　effects　of　high　temperature　and　strain　rate　on　the　failures　of　RC　beams.　In　the　method,　the　nonlinear　interaction　between　concrete　and　longitudinal　rebar　was　taken　into　account　by　using　a　bond-slip　relationship.　A　two-step　analysis　method　(thermal　transfer　analysis　followed　by　impact　analysis)　was　adopted.　Mechanical　analysis　was　carried　out　to　understand　the　failures　of　RC　beams　under　impact　loading　after　fire　exposure.　In　addition,　impact　responses　of　RC　beams　under　fire　exposure　and　after　cooling　down　were　compared　and　analyzed　under　different　fire　durations.　The　effects　of　impact　mass　and　velocity　on　the　impact　performances　of　RC　beams　after　fire　exposure　were　discussed.　It　is　found　that　the　proposed　meso-scale　numerical　model　can　effectively　simulate　the　failures　of　RC　beams　subjected　to　impact　loadings.　Under　impact　loadings,　RC　beams　after　fire　exposure　show　more　serious　damage　while　have　better　deformation　capacity　compared　to　the　RC　beams　at　room　temperature.　Fire　duration　has　a　significant　influence　for　the　impact　behaviors　of　RC　beams　no　matter　whether　they　are　cooled　down　or　not.　Compared　to　RC　beams　which　are　under　fire　exposure　for　＞　60　min,　specimens　after　cooling　down　are　subjected　to　less　damage　at　all　the　involved　temperatures.　The　difference　is　widening　along　with　the　increase　of　fire　duration.　Besides,　the　response　of　the　RC　beam　after　fire　exposure　is　affected　remarkably　by　both　impact　mass　and　velocity.