Silver (Ag) nanoparticles with an average size of ca. 10 nm were uniformly deposited on the surface of α‐Bi2Mo3O12 nanorods by using an ultrasound sonication method. Ultrasonic irradiation of preformed α‐Bi2Mo3O12 spherical nanoparticles (ca. 200 nm) in pyridine resulted in α‐Bi2Mo3O12 nanorods (ca. 100 nm diameter). Further, sonication of the mixture of α‐Bi2Mo3O12 nanorods and Ag2O in pyridine yielded a nanocomposite of α‐Bi2Mo3O12 nanorods with deposited Ag nanoparticles and pyridine. Calcination of the nanocomposite at 450 °C afforded pyridine‐free α‐Bi2Mo3O12 nanorods with deposited Ag nanoparticles. A plausible mechanism is proposed. The crystallized Ag nanoparticles are uniformly deposited on the surface, with bismuth (Bi) as the preferential binding site, as revealed by time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS). Structural, compositional and morphological characterization of the products is carried out by using transmission electron microscopy, energy‐dispersive X‐ray analysis, scanning electron microscopy, thermogravimetric analysis, X‐ray diffraction, X‐ray photoelectron spectroscopy and TOF‐SIMS. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)