ZnWO4 hollow clusters made up of nanorods were successfully prepared through a tripotassium citrate assisted hydrothermal process at 180 A degrees C. The hollow clusters' diameter was about 400 nm, and these clusters were made up of nanorods with a diameter of about 10 nm and a length of about 50 nm. X-ray power diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) were used to characterize the structure and morphology of the synthesized products. Based on experiments, the growth of these hollow clusters followed an aggregation-Ostwald ripening process. The photocatalytic activities for aqueous Rhodamine B of samples were investigated, and it was seen that ZnWO4 hollow clusters exhibited a strong photocatalytic activity.