Bismuth tungstate (Bi2WO6) has attracted great research interest as an important visible-light-responsive photocatalyst. In this paper, we report a facile hydrothermal route for the shape-controlled synthesis of micro/nanostructured Bi2WO6, without adding surfactants or templates. The results show that various morphologies of Bi2WO6 including coralloid spherical particles, packed nanosheets, fluffy microspheres, and plates can be obtained by adjusting the pH values of the precursors. The as-prepared porous fluffy microspheres with a hierarchical architecture synthesized at pH 8 exhibit the highest photocatalytic activity for the degradation of Rhodamine (RhB) under visible light irradiation. The photodegradation efficiency reaches as high as 99% within 20 min irradiation. This enhanced photocatalytic activity can be attributed to the unique porous structure and high BET surface area of fluffy microspheres with hierarchical architecture. (C) 2011 Elsevier Inc. All rights reserved.