US nanoparticles coating SrZrxTi1-xO3 (x = 0.27) microparticles were obtained by sonochemical reaction, and the as-prepared composites products were characterized by TEM, XRD, FT-IR and other techniques and the fabrication mechanism was also discussed. Moreover, the photocatalystic properties of the final products were investigated by degradation of methylene blue. By coating US nanoparticles, the absorption of the UV-Vis spectrum of SrZrxTi1-xO3 red-shifted, but the emission fluorescence spectrum blue-shifted. Adjusting the reactant concentration can control the thickness of the US layer. (C) 2003 Elsevier Science Ltd. All rights reserved.