Conducting polyaniline (PANI)/titanium dioxide (TiO2) composite nanofibres with an average diameter of 80-100 nm were prepared by one-step in situ polymerization method in the presence of anatase nano-TiO2 particles, and were characterized via Fourier-transform infrared spectra, UV/vis spectra, wide-angle X-ray diffraction, thermogravimetric analysis, and transmission electron microscopy, as well as conductivity and cyclic voltammetry. The formation mechanism of PANI/TiO2 composite nanofibres was also discussed. This composite contained similar to 65% conducting PANT by mass, with a conductivity of 1.42 S cm(-1) at 25 degrees C, and the conductivity of control PANT was 2.4 S cm(-1) at 25 degrees C. (c) 2006 Wiley Periodicals, Inc.