Polymer membranes have been successfully employed as a low-cost alternative for wastewater and water purification. The advantages of using polymer membranes include their physicochemical stability, processability, and mechanical performance. However, the intrinsic fouling process can block or compromise the performance of the membrane. In particular, the electrospun of polymer fibers has gained attention due to their high surface area, porosity and uniformity, offering enhanced working flux under similar conditions compared to conventional membranes. The recent challenges in the design of electrospun nanostructured membranes (ENMs) are related to the improvement of permeability, mechanical stability, selectivity, and longer half-life, where the use of nanostructured materials represents an innovative opportunity in the development of functional systems. The present chapter describes the analysis of the electrospun technique applied for the fabrication of ENMs, emphasizing the recent challenges and opportunities from the fiber morphology and nanomaterials incorporation, aiming to produce functional membranes for efficient wastewater and water filtration.