Dendritic polymer-modified porous silica particles prepared by poly(amidoamine) (PAMAM) dendrimer synthesis reaction were characterized by elementary analysis (EA) and size exclusion chromatography (SEC). EA demonstrated the successful alternate growth of dendritic layers on the particles. The phased growth of polymer moieties by cascade reactions filled pores on silica particle, and decreased M(lim)s. It was found that the pore-size distribution can be controlled by the generation number and the reaction conditions.