A simple method of synthesizing hybrid silver-polyacrylic acid-poly(N-vinylpyrrolidone) (Ag-PAA-PVP) nanogels was demonstrated through in situ reducing Ag+ inside PAA-PVP nanogels, which were formed by polymerization of acrylic acid in the PVP solution. Due to the ion exchange between Ag+ and acid protons of PAA, stable Ag+ clusters were formed inside the PAA-PVP nanogels, and hybrid nanogels were obtained by reducing Ag+ by ascorbic acid. Transmission electronic microscopic (TEM) images clearly showed the existence of silver nanoparticles inside the Ag-PAA-PVP nanogels. These hybrid nanogels showed typical surface plasma resonance absorption peak around 420 nm, and the size of the silver nanoparticles inside the Ag-PAA-PVP nanogels could be controlled from 9.5 +/- 1.6 nm to 1.9 +/- 0.4 nm by increasing the feeding amount of Ag+. In addition, these hybrid nanogels showed photoluminescent properties in fluorescent spectra. Considering the pH sensitive property of these hybrid nanogels, they will have potential application in drug delivery and biomedical imaging systems. +/- 2013 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.