Abstract: Monodisperse FeWO4 nanoparticles with specific spindle-like morphology have been synthesized in the presence of citric acid through hydrothermal process. In the synthesis route, citric acid played four roles such as the reducing agent, chelating regents, structure-directing agent and stabilizing agents. In addition, the morphology of FeWO4 was dramatically tuned by the pH value of the precursor medium. The optical properties of FeWO4 were investigated with UV–Vis spectra and photoluminescence spectroscopy. The photocatalytic experiments demonstrated that the decomposition efficiency of the monodisperse spindle-like FeWO4 nanoparticles is 74% after 30 min of UV irradiation, which displayed remarkable enhanced photodegradation activity compared with ordinary FeWO4 sample (57%) and normal TiO2 photocatalysts P-25 (56%).