Bi2WO6 microdiscs were synthesized via acetic acid-assisted hydrothermal process. The results revealed that the microdiscs were composed of numerous square nanoplates, and the nanoplates were stacked together through a side-by-side manner. The possible formation mechanism for the growth of microdiscs was discussed. The photocatalytic activity of the Bi2WO6 samples under solar-light irradiation was evaluated for degradation Rhodamine B (RhB). The as-prepared Bi2WO6 microdiscs exhibited excellent photocatalytic activity, and nearly 98% of RhB was degraded within 120 min, which was nearly 9 times than that of the products prepared by traditional solid-state reaction. The excellent photocatalytic performance can be attributed to porous structure and the higher surface area. (c) 2013 Elsevier B.V. All rights reserved.