An embedment of metal nanoparticles of well-defined sizes in thin polymer films is of significant interest for a number of practical applications, in particular, for preparing materials with tunable plasmonic properties. In this article, we present a fabrication route for metal-polymer composites based on cluster beam technique allowing the formation of monocrystalline size-selected silver nanoparticles with a +/- 5-7% precision of diameter and controllable embedment into poly (methyl methacrylate). It is shown that the soft-landed silver clusters preserve almost spherical shape with a slight tendency to flattening upon impact. By controlling the polymer hardness (from viscous to soft state) prior the cluster deposition and annealing conditions after the deposition the degree of immersion of the nanoparticles into polymer can be tuned, thus, making it possible to create composites with either particles partly or fully embedded into the film. Good size selection and rather homogeneous dispersion of nanoparticles in the thin polymer film lead to excellent plasmonic properties characterized by the narrow band and high quality factor of localized surface plasmon resonance. (C) 2016 Wiley Periodicals, Inc.