In this paper, we report a successful synthesis of monodisperse CaWO 4:Eu3+ superstructures by a surfactant-assisted hydrothermal process. The formation of the superstructures is strongly dependent on reaction parameters such as surfactant concentration, temperature and reaction time. The citrate concentration has significant influence in the resulting morphologies by selectively binding to the nuclei facets inducing preferential crystalline growth. In search of the formation mechanism of monodisperse CaWO4:Eu3+ superstructures, extensive characterization has been performed by using XRD, FE-SEM, TEM, HRTEM and SAED. The growth mechanism of monodisperse CaWO4:Eu3+ superstructures was proposed and their photoluminescence properties are discussed.