To　explore　the　shear-resistant　behavior　of　RC　beams　under　impact　load,　six　simply-supported　high　strength　RC　beam　with　various　shear　reinforcement　ratios,　were　tested　under　free-falling　drop-weights,　impacting　the　specimens　at　mid-span,　and　the　effects　of　impact　mass　and　impact　energy　on　the　shear　resistant　behavior　of　RC　beams　were　investigated.　The　crack　initiation,　propagation　and　the　failure　patterns　of　the　specimens　were　recorded　using　a　high-speed　video　camera.　The　characteristics　of　time　history　of　impact　force,　support　pressure　and　mid-span　displacement　were　described　in　details.　The　results　obtained　are　as　follows:　Experimental　studies　reveal　that　shear　mechanisms　play　an　important　role　in　the　overall　impact　behavior　of　RC　structures.　Severe　diagonal　shear　cracks　occur　even　with　statically　flexural-critical　RC　beams　tested　under　impact　loads　applied　at　the　mid-span.　Increase　of　concrete　strength　has　less　effect　on　the　degree　of　overall　failure,　but　it　can　reduce　the　specimen　local　failure　near　the　impact　loading　point;　This　article　summarizes　the　result　of　independent　impact　load　experiment　on　the　RC　beam.　It　draws　out　the　index　that　significantly　influences　between　the　maximum　mid-span　displacement　and　the　static　ultimate　bending　strength.　It　contributes　to　the　impact　resistance　design　method　for　simply-supported　RC　beam　performance　verification;　During　the　initial　stage　before　the　external　force　reached　the　supports,　the　impact　forces　acting　on　the　RC　beam　were　mainly　resisted　by　the　inertia　force　of　the　specimens.　The　stiffness　of　a　structure　and　the　span　length　of　a　beam　are　important　factors　in　resisting　impact　forces.　©,　2014,　Tianjin　University.　All　right　reserved.