Flowerlike bismuth oxychloride (BiOCl) was successfully synthesized by a simple and reliable template free hydrolytic method using Bi(NO3)35H2O as Bi source material at room temperature. The as-prepared samples were characterized by X-ray diffraction, field emission scanning electron microscope and UV–vis absorption spectrophotometer. The results indicated that the as-prepared BiOCl sample is self-assembled hierarchically with nanosheets. During the assembly of the BiOCl from nanosheets to microflowers, the reaction time plays an important role. The flower-like BiOCl showed much higher photocatalytic activity than commercial TiO2 (P25) in the degradation of Rhodamine B (RhB) dye under visible light irradiation due to its special structure.