A one-step solvothermal synthesis of hollow microspherical Bi2WO6 nanophotocatalyst was carried out for the first time under the collective action of potassium chloride (KCl) and polyvinylpyrrolidone (PVP). The physicochemical properties such as crystal structure, morphology, specific surface area, and optical properties of the material were characterized by means of XRD, SEM, EDS, UV-vis, and BET. The effect of KCl and PVP on the morphology control of the product is discussed. Rhodamine B dye in wastewater was used as model pollutant, and the effect of hollow microspherical morphology on photocatalytic activity is discussed. The results presented here provide a simple, effective, and widely applicable approach for the rapid synthesis of special morphology Bi2WO6 by a one-step method.