Drinking water shortage is worsening. Capacitive deionization (CDI) of saltwater has gained attention due to its low energy consumption and environmental friendliness. A single anion exchange membrane (AEM) can selectively move anions to positive electrodes for better desalination performances. Poly(diallyldimethylammonium chloride)-functionalized reduced graphene oxide (PrGO) serves as an AEM for CDI. The AC and PrGO coated AC electrode pair (AC‖PrGO/AC) for CDI of saltwater under + 1.5 V for 1 h reaches a high optimized-salt removal and electrosorption capacity. This work presents the feasibility using the high-efficiency and facile PrGO anion-selective thin film layer served as an AEM analog for a simplified and low-cost membrane-CDI process to enhance desalination performances for potential water recycling and reuse from salt, inorganic waste or metal-contaminated ground waters.