In the electroless plating process, to omit a sensitizing process with SnCl2, we utilized amino-functional groups on polymer particles. At first, highly in monodisperse functional polymer particles could be prepared by a two-step seeded polymerization of styrene, divinylbenzene, and glycidyl methacrylate. Then, surface epoxy-functional groups were converted to amino-functional groups by treating the particles with a diamine. By using these surface amino functionalities, we tried to prepare uniformly metal-coated monodisperse polymer particles by electroless plating method. The constituents of an electroless nickel solution bath are nickel salt, a reducing agent, suitable complexing agents, and stabilizers. And the metal thickness was simply controlled by changing the loading amount of substrate polymer particles. Morphological observation of nickel-plated polymer particles was conducted by using optical microscopy, scanning electron microscopy, and transmission electron microscopy. The structural composition of plated nickel was also investigated. Most of all, the function and the efficiency of the amino-functional group of polymer particles as a polymeric ligand for metal binding was elucidated. From all observations, it was evident that in the electroless metal plating process without any sensitization step, the deposition of metal clusters on substrate particles is largely dependent upon the particle surface functionality. (c) 2006 Wiley Periodicals, Inc.