The Split Hopkinson Pressure Bar (Split Hopkinson Pressure Bar, SHPB) test was done to investigate the dynamic properties of crumb rubber modified asphalt concrete under impact loading. Test results and analyses have indicated that the addition of rubber can notably increase the plasticity of asphalt concrete. Both dynamic strength and impact toughness are functions of temperature and strain rate. The strength and toughness have higher values at 25 ℃ than those at -20 ℃ and 60 ℃ while increasing monotonically with the increase of strain rate. The addition of rubber can enhance the strength and toughness of the material by more than 200% and nearly 200%, respectively. The superior performance of rubber modified asphalt concrete under impact loading comes from the "stone-rubber-stone", i.e., rigid-flexible- rigid, contact made in asphalt concrete. There exists an optimized rubber with respect to the anti-impact performance of the material, which is about 20% by the mass of asphalt binder.