NanoSiO2 appears to be one of the most attractive nanomaterials for cement and concrete researchers, however dispersion of nanoSiO2 and excessive shrinkage induced by nanoSiO2 limit its effective use.The surface modification technology can be introduced to improve nanoSiO2 property.In this study, at first, nanoSiO2 -shrinkage reducing agent (SiO2@SRA) core-shell nanoparticles was synthesized from shrinkage reducing agent and colloidal nanosilica by electrostatic self-assembly methods, SiO2@SRA was testified by DLS, FTIR,and TGA.Next, the effect of SiO2@SRA on the performance of cement-based composites was investigated.The results show that SiO2@SRA-added composites experience a higher rate of strength increase than that of nanoSiO2, and shrinkage property of cement-based composites can be regulated by shell structure.Separation of shell and core particle of SiO2@SRA in pore solution is a possible mechanism of shrinkage-reducing observed in composites.The research provides a new pathway for nanoSiO2 to optimize cement-based composites.