In this study, SiO2 nanoparticles have been dispersed selectively into the PS (polystyrene) microdomain of PS-b-PMMA (polystyrene-blockpolymethylmethacrylate) by blending the polymer with PS-tethered SiO2 nanoparticles.Through the observation from AFM (Atom Force Microscopy) and SEM (Scanning Electron Microscopy), the SiO2 nanoparticles not only distribute uniformly in the PS domain but also enlarge the size of the PS domain and transform the morphology into a specific islanded microstructure.However, any excessive SiO2 or SiO2 particles with a size larger than the PS domain would constrain the rearrangement and cause an unobservable separation.