The Masked Water-tyrant (Fluvicola nengeta) is a species of bird in the Tyrannidae family, the tyrant flycatchers. It is found in its major range in eastern and southeastern Brazil in the caatinga and extreme eastern cerrado, and also Atlantic coastal regions; a second smaller disjunct range occurs on the Pacific side of South America in western Ecuador, and coastal border regions of northwest Peru. Its natural habitats are subtropical or tropical mangrove forests, subtropical or tropical moist shrubland, and heavily degraded former forest.