The MoS2 nanowires with diameters of 4 nm and lengths of 50 nm were synthesized by a hydrothermal method using 0.36 g MoO3 and 1.8 g Na2S as precursors in 0.4 mol/l HCl solution at 260degreesC. The products are characterized by XRD XPS, TEM, HTEM and BET. Results show that the as-prepared MoS2 nanowires consist of 1-10 sulfide layers with BET surface areas of 107 m(2)/g. The possible reaction route and the formation mechanism of the MoS2 nanowires are discussed. The effects of exterior conditions such as pH value, temperature, concentration of precursors and additives on the particle size and morphology of MoS2 crystallites were investigated. (C) 2003 Elsevier Science B.V. All rights reserved.