gamma-Irradiation has been used to prepare nanocrystalline composites-CdS/polyacrylamide with 18 wt % cadmium sulfide at room temperature, in which the inorganic phase displays uniformity of size and nearly uniform dispersion. The formation of nanocrystalline CdS and the polymerization of acrylamide are in a single step. X-ray Powder Diffraction and Infrared Spectra were used to characterize the product. Its morphology was determined by Transmission Electron Microscopy.