The mechanochemical synthesis of NaNbO3 is Studied. It is shown that NaNbO3 can be prepared by milling the constituents, i.e. Na2CO3 and Nb2O5 in the planetary mill. After 40 h of mechanochemical treatment NaNbO3 nanoparticles in the range of 10-20 nm are obtained. Furthermore, the high-energy milling leads to the mechanochemically-triggered carbonate decomposition, which has been observed for a few cases in the open literature. (C) 2004 Elsevier Ltd. All rights reserved.