In　order　to　study　the　flexural　impact　behavior　of　Crumb　Rubber　Concrete　(CRC)　beams,　Coarse　crumb　rubber　and　fine　crumb　rubber　is　used　to　prepare　CRC,　and　three　kinds　of　interfacial　modifiers　(X,　Y,　KH550)　are　chosen　to　modify　CRC.　The　test　results　show　that　the　initial-crack,　fracture　impact　cycle　number　of　concrete　are　improved　by　incorporating　of　coarse　rubber,　and　are　decreased　by　incorporating　of　fine　rubber.　The　flexural　impact　behavior　of　CRC　modified　by　interfacial　modifiers　increases　significantly.