In this reaserch, photocatalyst silver titanium dioxide was doped and modified by Polyethylene Glycol (PEG). The purpose of the present study was to analyse the synthesized Ag/TiO2 thin film doped and undoped PEG. Ag/TiO2 thin films on silicon wafer have been prepared by sol-gel spin coating. The samples were characterized by Grazing Incidence X-ray diffraction (GIXRD), Field Emission Scanning Electron Microscopy (FESEM) and Atomic Force Microscope (AFM). The doped and undoped PEG Ag/TiO2 thin films showed a mesoporous TiO2 matrix which includes TiO2 crystallites of 10-20 nm in size and small Ag nanoparticles (white spots) with various sizes ranging from 10 to 30 nm. However, doped PEG Ag/TiO2 thin film showed the Ag nanoparticles became agglomerates but still remained roughly uniform on the surface.