A 100mm-diameter split Hopkinson pressure bar (SHPB) was applied to investigate effects of nanoparticles on the dynamic mechanical properties of recycled aggregate concrete (RAC) under impact loading. The nano-SiO2 (NS) and nano-CaCO3 (NC) were incorporated to replace cement by mass of 1 and 2% in RACs. The impact velocities were set as 7.7, 9.8 and 11.6m/s in the SHPB tests. The effects of nanoparticles on failure patterns, compressive strengths, elastic modulus, peak strain and dynamic increase factor (DIF) of RACs under different strain rates were analyzed and discussed. The results show that nanomodified RACs exhibit higher both quasi-static and dynamic compressive strengths compared to control RAC. Dynamic elastic modulus of RAC seems not be affected by nanoparticle dosages and impact velocities. Compared to NC, NS is more effective to improve dynamic compressive strengths of RAC. On the other hand, the nanoparticles modified RACs exhibit lower DIF values than that of the control RAC. Moreover, NC obviously more reduces the DIF values of nanomodified RAC than NS. Display omitted •Nano-SiO2 and nano-CaCO3 modified recycled aggregate concrete (RAC) exhibit higher dynamic compressive strength compared to the control RAC.•Nanoparticles can reduce the strain rate sensitive of cement mortar in RAC, and then decrease the dynamic increase factor.•Compared to nano-CaCO3, nano-SiO2 more effectively improves the dynamic compressive strength of RAC, but less obviously enhances the deformation capacity.