Titanium oxynitride (TiOxNy) with varying nitrogen contents assembled in the pores of mesoporous material has been achieved by nitriding titania-modified MCM-41 under flowing NH3 atmosphere. XRD, XPS, N-2 adsorption-desorption isotherms and UV-Vis spectra are employed to characterize the structure of the composite materials. The results show that titanium oxynitride is formed and crystallized at 700 degreesC when the nitridation time is 3 h. The MCM-41 host is also nitrided inevitably, while the mesostructure is still preserved. The effects of nitridation temperature on the formation of titanium oxynitride and structure of MCM-41 are systematically discussed. (C) 2004 Elsevier B.V. All rights reserved.