Sulfur/carbon nanocomposites have been successfully prepared by a solution-based processing technique using dimethyl sulfoxide as the solvent. The as-prepared nanocomposites were characterized by X-ray diffraction and field emission scanning electron microscopy. The electrochemical performance of sulfur/carbon nanocomposites were tested by cyclic voltammetry and galvanostatic charge/discharge cycling. When applied as the cathode material in lithium sulfur batteries, the as-prepared sulfur/carbon nanocomposites exhibited a high reversible capacity of 1220mAhg−1 in the first cycle and maintained a satisfactory cyclability. This drastic improvement of specific capacity and cycling performance could be attributed to the reduced particle size of sulfur and the homogeneous distribution of sulfur nanoparticles on a carbon matrix, resulting from this novel solution-based processing technique.