Carbon materials have the advantages of good electrical conductivity and excellent chemical stability, so many carbon materials have been introduced as electrodes for the capacitive deionization (CDI) process. Due to the low surface area compared to the other nanocarbonaceous materials, CNFs performance as electrode in the CDI units is comparatively low. This problem has been overcome by preparing high surface area carbon nanofibers and by creating numerous long pores on the nanofibers surface. The modified CNFs have been synthesized using low cost, high yield and facile method; electrospinning technique. Stabilization and graphitization of electrospun nanofiber mats composed of polyacrylonitrile (PAN) and poly (methyl methacrylate) (PMMA) leads form longitudinal pores CNFs. The utilized characterizations indicated that the CNFs obtained from electrospun solution having 50% PMMA have surface area of 181 m²/g which are more than the conventional CNFs. Accordingly, these nanofibers revealed salt removal efficiency of ~90% and specific capacitance of 237 F/g.