Si/C composite nanofibers were prepared by electrospinning and carbonization. Two surfactants: cetyl trimethyl ammonium bromide (CTAB) and sodium dodecanoate (SD), were used to improve the dispersion of Si nanoparticles and the electrochemical performance. Results show that after 50 cycles, the discharge capacity of Si/C nanofibers does not have significant change after the addition of CTAB surfactant, however, the discharge capacity of Si/C nanofibers with SD surfactant is more than 20% higher than that without surfactant. It is demonstrated that employing SD surfactant is a simple and effective way to obtain Si/C nanofibers with large capacities and good cycling stability. (c) 2012 The Electrochemical Society. All rights reserved.