CuInSe(2) powders were successfully prepared using the water-in-oil microemulsion-mediated solvothermal process. The formed micelles in the water-in-oil microemulsion system acted as nanosized reactors to restrict the growth of CuInSe(2) powders. The distances between the constituent reactants were shortened, thereby leading to an increased reaction rate and shortened required reaction time. The reaction temperature in the microemulsion route was significantly lowered with the assistance of the solvothermal treatment. The microemulsion-derived CuInSe(2) powders exhibited a spherical shape and were much smaller than the powders prepared via the conventional solvothermal process. The particle sizes of the obtained powders were around 5-15 nm. As the reaction temperature was elevated, the crystallinity and the particle size were also increased. (C) 2010 Published by Elsevier B.V.