This work demonstrated a facile route to the synthesis of polyaniline (PANI) nanofibers by polymerization of aniline using chloroaurate acid (HAuCl4) as the oxidant. The reduction of AuCl4- is accompanied by oxidative polymerization of aniline, leading to uniform PANI nanofibers with a diameter of 35 +/- 5 nm and aggregated gold nanoparticles which can precipitate from the liquid phase during the reaction. The resultant PANI nanofibers and gold particles were characterized by means of different techniques, such as UV-vis, FTIR spectroscopy, and scanning and transmission electron microscopy methods. It is found that the gold aggregates are capped with polyaniline, and the conductivity of the fibers is around 0.16 S/cm.