The influence of gold nanoparticles (GNPs) and gold nanodots (GNDs) on fluorescence properties of hyperbranched poly(amidoamine)s (HPAMAMs) which were synthesized by Michael addition of 1-(2-aminoethyl) piperazine (AEPZ) and methyl acrylate (MA) was investigated in this study. It was found that GNPs with definite surface plasma absorption can quench the fluorescence of HPAMAMs. With the increasing of the concentration of GNPs, the fluorescence intensity of HPAMAMs decreased correspondingly, and varied linearly at low concentration of GNPs. This phenomenon was owing to the fluorescence resonance energy transfer (FRET) between the HPAMAMs and GNPs. In contrast, the complex with smaller GNDs encapsulated in the interior of the HPAMAMs presented greatly enhanced emission. Those results show that the size of nano golds may be used to adjust the fluorescence properties of HPAMAMs and may extend potential applications of HPAMAMs and GNPs. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 2386-2391, 2010