A new method for the preparation of crystalline mesoporous niobium-silicon oxynitride (NbSiON) by the straightforward technique is described. The characterization has been performed by various techniques showing that the material has: (i) the specific surface area of 160 m(2) g(-1) and mesopores centered at 4.0 nm from N-2 adsorption, (ii) the crystalline walls from wide-angle XRD pattern, (iii) the wormhole-like framework from low-angle XRD pattern and TEM images, (iv) the nanobelts and nanowires morphology from TEM images, and (v) Si-O-Nb and Si-N-Nb bonds from FTIR spectroscopy. (c) 2006 Elsevier B.V. All rights reserved.