CdS nanowires with an average diameter of 25 mn and lengths of 20-40 mu m have been solvothermally synthesized in a mixed solvent of ethylenediamine and dodecanethiol at 180 degrees C. The time-dependent examinations reveal that the formation process of CdS nanowires involves two sequential processes: a short-period solid-solid transformation process in the initial stage and a long-period Ostwald ripening process. The effect of both the volume ratios between the two components of the solvent and the reaction temperatures on the nanowire growth has also been investigated in detail. The results of the photoluminescence and UV-vis spectroscopy measurements reveal that the as-prepared CdS nanowires show a quantum confinement effect.