Summary This Thesis Contains Four Main Chapters : Chapter I: This chapter contains the general introduction of nanomaterial and its dimensions (zero, one, two and three dimensions). Properties of nanomaterials and quantum size effects "confinement" have been mentioned. Synthesis of nanomaterial by different chemical and physical methods such as (mechanical, chemical vapor deposition, sol-gel, electro deposition, electrostatic selfassembly and hydrothermal method) were reviewed. Some applications of nanomaterial and literature survey were described. Preparation of gold and silver nanoparticles and its application on a photocatalytic process as well as the aim of this work was surveyed. Chapter II Fundamental theoretical of the devices used in the characterization processes of the as prepared samples especially, transmission electron microscope (TEM), ultraviolet – visible spectrometer (UV-VIS) and Fourier transform infrared spectrometer were described in details. The electronic transition, vibrational mode and its relation with the incident energy of the UV-VIS and IR spectra were explained. Chapter III Chemicals detail of materials that used in the synthesis of gold and silver nanoparticles were written. The synthesis of gold and silver nanoparticles using gold (III) chloride hydrate, silver nitrate with sodium citrate as a surfactant stabilizing materials in the presence of sodium borohydried as a reducing agent at room temperature was discussed. Preparation of (gold/silver) alloy nanoparticles using different molar ratio of gold (III) chloride hydrate and silver nitrate in the presence of sodium citrate as a surfactant at high temperatures was carried out. The preparation of the as prepared samples in the photocatalytic processes of 4-nitrophenol was described. Preparation of the polyacrylamide film doped with different concentrations of (Au/Ag) alloy nanoparticle was concluded. The components of TEM, UV-VIS and FTIR devices and its images were obtained.