In this paper, we report the obtention of CaWO4 crystals with controlled morphologies, such as spindle-like, nanorods, urchin-like, and sphere-like, were selectively synthesized via a simple sonochemical method without any surfactants or templates. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy and high-resolution transmission electron microscopy. It is found that the ultrasonic time and pH value played an important role in the morphology-controlled synthesis of CaWO4 crystals. The possible mechanism for the formation of CaWO4 samples with different shapes was discussed in detail. (C) 2013 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.