We demonstrated a simple, one-step route for assembling Au nanoparticles (NPs) on N-containing polymer nanospheres through in situ reductive growth process.Using resorcinol-melamine-formaldehyde resin nanospheres (RMF NSs) as a functional platform, neither a surfactant/ligand nor pretreatment is needed in the synthetic process of Au@RMF NSs hybrid nanostructure. When used as a catalytic media for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol, the Au@RMF NSs hybrid nanostructures show significantly enhanced catalytic performance than the ever reported Au-based catalyst. The absorption modal of 4-NP on this nanostructure is also discussed by theoretical calculations using density functional theory. The calculated results verify the preferential capture of 4-NP by the N-containing functionalities of RMF NSs, which is critical step for the acceleration of Au-based catalytic reaction kinetics, leading to the remarkable improved catalytic behavior. The superior features of RMF NSs as well as minimal economical cost compared with other polymer and non-polymer will promote further interest in the field of N-containing catalysis.