Formation of colloidal dispersions is the most attractive and efficient method which can improve the inherent insoluble and intractable properties of polypyrrole. Polyoxyethylene nonylphenyl ether sulfate (NPES), a novel bifunctional polymeric surfactant which has both anionic and non-ionic active groups, was used as both the template and the dopant in the chemical oxidative polymerization of pyrrole in the present work. The size of the NPES doped polypyrrole nanoparticles (PPy/NPES) decreased and their water-dispersion stabilities increased with the increasing of the feeding ratio of NPES. The PPy/NPES nanoparticles possess high electrical conductivity at room temperature and the weak temperature dependence of the conductivity. The conductivity-temperature heating curves are discussed. (C) 2011 Elsevier B.V. All rights reserved.