In order to clarify the influence of curing temperature on the impact mechanical characteristics of steam cured concrete applied for typical prefabricated components of high speed railway, the destructive form, stress strain relationship and strain rate effects on C60 steam cured concrete mixed with fly ash and slag under different strain rates and four curing temperatures were investigated by split Hopkinson pressure bar(SHPB) test. The fineness module which was used to evaluate the degree of concrete breakage under different strain rates was proposed. The effect of curing temperature on the impact mechanical properties of concrete was analyzed. The results show that the peak stress of steam cured concrete increases with the increase of strain rate, while the peak strain shows a decreasing trend, the fineness module of broken concrete particles decreases, and the degree of fracture increases significantly. With the increase of curing temperature, the peak stress of the steam cured concrete decreases significantly, and the steam cured concrete shows a higher strain rate sensitivity. The established concrete constitutive model considering the strain rate agrees well with the experimental stress strain curves. The higher temperature steam curing condition leads to an increase in internal defects of the concrete, which makes the impact mechanical properties different from the standard cured concrete.