Nanocrystalline CuS powders with spherical, quadrate, plate-like and tubular morphologies have been synthesized via hydrothermal treatment of Na(2)S(2)O(3)(.)5H(2)O and different copper sources (including CuO, CuSO(4)(.)5H(2)O and CuCl(2)(.)2H(2)O) in water at 130-170degreesC for 6-24 h. The morphology and size of the obtained products can be well controlled simply by adjusting the copper sources, reaction temperature and reaction time. The possible formation mechanisms of nanocrystalline CuS powders from different copper sources and NaS(2)O(3)(.)5H(2)O during the hydrothermal processing were also proposed. (C) 2004 Elsevier B.V. All rights reserved.