In this paper, nanostructured silver with an average crystallite size of 28 nrn and internal strain of 0.44% was synthesized by mechanochemical reduction of Ag2O using graphite in a high energy planetary ball mill. XRD, SEM and TEM techniques were used to characterize the structural evolution and morphological changes of products. The results showed that the reaction is progressed by a nucleation and growth mechanism process. Although the changes of crystallite size and internal strain in Ag2O were regular during the milling, there was an irregularity in the aforementioned parameters of Ag particles. This irregularity was probably owing to the progressive generation of silver during the milling. (C) 2011 Published by Elsevier BM, on behalf of The Society of Powder Technology Japan. All rights reserved.