A composite of polythiophene (PT) and nano-titanium dioxide (TiO2), possessing core-shell structure, was synthesized via Oxidative polymerization of thiophene Using Fecl(3) in the presence of three different surfactants: anionic, cationic, and nonionic. The morphology of the obtained composite materials was investigated by SEM, proving the core-shell structure of the prepared nanocomposite. The formal-ion thermal stability of the PT onto TiO2 nanoparticles were confirmed by FTIR and TGA analyses, respectively, XRD data show all of composite materials were amorphous structures. The electrical properties of the nanocomposites were investigated in the presence of surfactant materials. and the best semiconductor property was observed for PT/TiO2-amionic system. This difference in the conductivity has been attributed to differences in the stability of the composites. (C) 2008 Elsevier B.V. All rights reserved.