Because of their high specific surface and controllable structure and porosity, electrospun porous ultrafine fibers could be potentially used as drug delivery system. Therefore, the focus of this work is to prepare various electrospun porous polyethersulfone (PES) fibers via different methods and then study their drug release behavior in case of a natural medicine named curcumin chose as the model drug, Scanning electron microscopy (SEM), thermo gravimetric analyzer (TGA) were employed to determine the morphology, content, and porosity of fiber, respectively. UV-vis spectrophotometer was used to record the drug delivery behavior with time. The results showed that both the surface and the internal structures of all the ultrafine PES fibers were porous but the ones made by liquid-liquid method have the largest porosity. TGA results indicated that the drug content in the fibers was almost all the same with that of in the initial solution. Besides, the fibers produced by liquid-liquid method exhibited the most stable release speed and the largest release amounts compared with the fibers produced by other methods in this paper. All of these results revealed the porous electrospun fibers could be used as advanced drug delivery system. Keywords: Porous, Liquid-liquid method, Two-step method, Drug release