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Abstract Sodium superionic conductor (NASICON)‐type materials are getting more and more attention due to their high capacity and good cycling ability compared with other cathode materials in aqueous zinc ion batteries (AZIB). The present paper was to study the synthesis and electrochemical properties of two NASICON compounds of Na₃V₂(PO₄)₃and Na₃V₂(PO₄)₂F₃and to understand the impacts of fluorine. Both Na₃V₂(PO₄)₃and Na₃V₂(PO₄)₂F₃are synthesized by hydrothermal growth followed with annealing at 800°C in inert gas. With 3 mol/L Zn(CF₃SO₃)₂in water as electrolyte, Na₃V₂(PO₄)₃offered a high storage capacity, while Na₃V₂(PO₄)₂F₃demonstrated a high discharge voltage though low storage capacity. It was also found that the storage capacity of Na₃V₂(PO₄)₂F₃increases with increased cycles; however, the compound undergoes a gradual phase transition. It is discussed possible approaches to attain both high discharge voltage and large capacity with good cycling stability.